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San Francisco, California 


of the 

Society of Motion Picture Engineers 



Report of the President LOREN L. RYDER 1 

New York Motion Picture Production 


New One-Strip Color-Separation Film in Motion Picture Produc- 

A New Variable- Area Recorder Optical System 

Cathode-Ray-Oscillograph Images of Noise-Reduction Envelopes 

B. H. DENNEY 37 

A Motion Picture Film-Developing Machine . . R. PAUL IRELAND 50 

Television Remote Operations A. H. BROLLY 54 

Sound Motion Pictures for Passenger Trains .... JOHN G. BITEL 64 

Improved Film Splicer MICHAEL S. LESHING 68 

A New Slidefilm Projector J. McWiLLiAMS STONE 74 

Arthur S. Dickinson 77 

62nd Semiannual Convention 78 

Sections 87 

Office Staff 87 

Purely Personal 88 

Society Announcements 90 

Current Literature . . 94 


Chairman Editor Chairman 

Board of Editors Papers Committee 

Subscription to nonmembers, $10.00 per annum; to members, $6.25 per annum, included in 
their annual membership dues; single copies, $1.25. Order from the Society's general office. 
A discount of ten per cent is allowed to accredited agencies on orders for subscriptions and 
single copies. Published monthly at Easton, Pa., by the Society of Motion Picture Engineers, 
Inc. Publication Office, 20th & Northampton Sts., Easton, Pa. General and Editorial Office, 
342 Madison Ave., New York 17, N. Y. Entered as second-class matter January 15, 1930, 
at the Post Office at Easton, Pa. under the Act of March 3, 1879. 

Copyrighted, 1948, by the Society of Motion Picture Engineers, Inc. Permission to republish 
material from the JOURNAL must be obtained in writing from the General Office of the Society. 
The Society is not responsible for statements of authors or contributors. 

Society of 

Motion Picture Engineers 

342 MADISON AVENUE NEW YORK 17, N. Y. TEL. Mu 2-2185 



Loren L. Ryder Clyde R. Keith 

5451 Marathon St. 233 Broadway 

Hollywood 38, Calif. New York 7, N. Y. 

Donald E. Hyndman William C. Kunzmann 

342 Madison Ave. Box 6087 

New York 17, N. Y. Cleveland, Ohio 

Earl I. Sponable G. T. Lorance 

460 West 54 St. 63 Bedford Rd. 

New York 19, N. Y. Pleasantville, N. Y. 



John A. Maurer James Frank, Jr. 

37-01 3 L St. 356 W. 44 St. 

Long Island City 1, N. Y. New York 28, N. Y. 


Ralph B. Austrian 
247 Park Ave. 
New York 17, N. Y. 


John W. Boyle Charles R. Daily 

1207 N. Mansfield Ave. 5451 Marathon St. 

Hollywood 38, Calif. Hollywood 38, Calif. 

Robert M. Cor bin David B. Joy 

343 State St. 30 E. 42 St. 

Rochester 4, N. Y. New York 17, N. Y. 

Hollis W. Moyse 

6656 Santa Monica Blvd. 
Hollywood, Calif. 


William H. Rivers S. P. Solow 

342 Madison Ave. 959 Seward 

New York 17, N. Y. Hollywood, Calif. 


Alan W. Cook Gordon E. Sawyer 

4 Druid PI. 857 N. Martel 

Binghampton, N. Y. Hollywood, Calif. 

Paul J. Larsen 

Los Alamos Laboratory R. T. Van Niman 

Lloyd T. Goldsmith University of California 4431 W. Lake St. 

Burbank, Calif. Albuquerque, N. M. Chicago, 111. 

Section Chairmen and Secretary-Treasurers listed on page 87. 
Office Staff listed on page 87. 

Report of the President 

THIS is THE semiannual report of the president to the members of 
the Society of Motion Picture Engineers. It is a statement of 
activities subsequent to the report submitted at the 61st Semiannual 
Convention of the Society in Chicago and published in the July, 1947, 
issue of the JOURNAL. 

The Society now has a new home a four-room suite on the ninth 
floor of the Canadian Pacific Building, 342 Madison Avenue, New 
York 17, N. Y. The entrance room number is 912 and the telephone 
number is Murray Hill 2-2185. There is a big "WELCOME" mat 
out to all members and friends. We want you to become better ac- 
quainted with our staff and to use these facilities. They are yours as 
members of this organization. 

We enjoyed our long tenancy at the Hotel Pennsylvania and were 
sorry to leave its many conveniences but we had outgrown our old 
quarters and the hotel could not give us more room. 

Our staff has both changed and grown. Harry Smith, Jr., who 
served the Society during the war, has resigned to go into business for 
himself. Mr. Boyce Nemec has now been promoted to executive 
secretary. As you will recall, he joined the Society as engineering 
secretary upon his release from the Army's Signal Corps Photo- 
graphic Division. He is doing a grand job. He is assisted by the 
new staff engineer, Mr. Thomas F. Lo Giudice; the JOURNAL editor, 
Miss Helen Stote; and Miss Margaret C. Kelly, office manager. In 
our office staff we also have Miss Beatrice Melican, Mrs. Silvya 
Morrow, Miss Dorothy Johnson, and Miss Helen Long. We are 
proud of this organization. 

The Society membership has now reached a new high of 2760 mem- 
bers. The member's equity in the Society is $99,314.30 as of October 
1, 1947. The sustaining membership under the chairmanship of our 
past-president, Mr. Donald E. Hyndman, now includes 42 companies 
which have expressed their interest in our activities by contributing 

* Presented October 20, 1947, at the SMPE Convention in New York. 


2 RYDER .January 

At the Chicago Convention I reported that the scope of the Society 
had been denned to include all phases of pictorial rendition of action 
whether it be from film, as in motion pictures, or from electronics, as 
in television. The Society's facilities and staff are now prepared to 
handle this great field of activity and to be of greater service to more 
people. I am sure that each of you knows at least one person who can 
both contribute and profit by being a member. This is not an open 
plea for new members, for it is our desire to retain the high standard 
of our membership. We do wish, however, to bring within the fold 
of our organization all people who should rightfully be associated 
with us. 

We now have the Atlantic Coast Section in New York, the Midwest 
Section in Chicago, the Pacific Coast Section in Hollywood, and a 
Student Chapter at the University of Southern California in Los 
Angeles. Since it is a part of our duty to aid in the training program 
of young engineers, plans are under way for more Student Chapters 
at worthy institutions of higher learning. 

Every major move that has been made by the Society has been 
made after careful consideration by the Board of Governors. As 
president of the Society and as chairman of the Board meetings, I call 
your attention to the fact that expansion entails increased responsi- 
bilities, financial and otherwise. As of this date our revenue, includ- 
ing sustaining membership, and our operating expense are about 
equal. We may show r a deficit this year because of furnishing our new 
offices. Next year we should again show a 10 per cent or more excess 
of revenue over expense or we should curtail some of our activities. 
More members or more sustaining funds is, of course, the best answer. 

The papers program for the 62nd Semiannual Convention, as for 
the 61st Convention in Chicago, was oversubscribed. We regret 
that convention time permitted the presentation of only those papers 
having greatest topical interest or the papers first to be submitted. 
It is our desire that our membership gain full advantage of all techni- 
cal information through our JOURNAL and I want to encourage you to 
present more and more manuscripts for publication, even though 
time may not permit their presentation at conventions. 

Few people realize that the JOURNAL OF THE SOCIETY OF MOTION 
PICTURE Engineers is the one and only up-to-date and authoritative 
technical publication covering all phases of PICTORIAL RENDITION OF 
ACTION. We are proud to announce that in our postwar recovery our 
September issue went to press in September and shortly you will 


receive the JOURNAL of the month during the first week of the 

Your engineering vice-president, Mr. John A. Maurer, has con- 
tinued to do a colossal job. At the request of the American Standards 
Association and with the approval of the Board, the Society jointly 
with The Institute of Radio Engineers has undertaken a special assign- 
ment in standardization of sound recording, including film, disk, and 
magnetic methods. This can be of great aid to all manufacturers and 
users of recording equipment. We expect that our Society will be in 
the same important position in regard to all large-screen television. 

The theaters and the producers as a group have been slow in heed- 
ing the warning of the engineers in regard to theater television but 
individually there has been an awakening. Several producing com- 
panies have now taken out licenses and several others will follow. 
Our efforts in this respect as presented in last year's report have not 
been in vain. 

I can now predict with assurance the great success of this our 62nd 
Semiannual Convention and Theater Engineering Conference. The 
credit for this undertaking and its success goes to our ever-efficient 
convention vice-president, Mr. W. C. Kunzmann, the Atlantic Coast 
Section chairman, Mr. James Frank, Jr., and the many persons who 
have contributed so liberally of their time and effort. 

Between the time of the April report and this report, your president 
has been appointed to the American National Film Committee of the 
United Nations for which your past-president, Mr. D. E. Hyndman, 
is acting as representative. Your president has also been appointed 
to the Motion Picture Committee of the American Heritage Founda- 
tion with which I am sure you are all familiar. 

By action of the Board of Governors of the Society the 63rd Semi- 
annual Convention is to be held at the Santa Monica Ambassador 
Hotel and Del Mar Beach Club, May 17 to 21, inclusive. This con- 
vention will be general in its scope. Please be among those present 
we shall make it worth your while. 

Respectfully submitted, 

LOREN L. RYDER, President 

New York 

Motion Picture Production* 



THERE HAVE BEEN many news articles with reference to the 
problem of motion picture production in the City of New York, 
and many of them, I fear, used the language of the West Coast by 
reason of the extravagance of the adjectives used. Our approach 
has been a simple and a modest one. It is an approach that I think 
any people residing in any city, who have an interest generally in 
the welfare of that city, would take with reference to a business to 
which it feels it can contribute substantially. We do not envision 
lifting Hollywood from the West Coast and dropping it into New 
York City. That would be ridiculous and we realize and know that 
only too well. We do believe that we have many things here that 
this industry needs and we feel that the City of New York is entitled 
to and properly should be given a greater percentage of the production 
of pictures and that if the facilities, if our scenes, if our backgrounds, 
if that which we have to contribute are utilized by the industry, it 
will result not in bitter competition between the West Coast and 
New York City, or competition between any other center of produc- 
tion and New York City, but it will serve as a stimulant which will 
bring improvement to the motion picture industry. 

Some of the problems with which we were confronted were these: 
For the past year and a half, many people have spoken to the Mayor 
with reference to bringing motion picture production or a greater 
percentage of it to the City of New York. It was only early in July 
that Mayor O'Dwyer decided the time had arrived when a special 
survey should be made of the needs of the industry and that it should 
include a study of the respects in which we of the City of New York 
had been remiss and failing to co-operate with the industry. 

* Presented October 20, 1947, at the SMPE Get-Together Convention Luncheon 
in New York. 



We found that we had some shortcomings. We learned that by 
inviting the independent producers and the major companies to confer 
with us and requested their very sincere and direct comments and 
criticism of how we had been conducting ourselves. We found out 
this: Many of the laws, the rules, the regulations we had on the 
books in the City of New York gave no consideration to the needs of 
the motion picture industry. There had never been a study of what 
the needs of the industry were. We found that laws were on the 
books which were designed to cover electric construction in buildings, 
and, as motion picture production companies came to New York 
those laws were being applied to them. 

There were many unreasonable restraints and restrictions involved 
in those laws. We found, too, that even with reference to the is- 
suance of permits for the taking of outdoor scenes we were tied up in 
terrible red tape, that we were imposing unreasonable restrictions on 
the industry. 

We have had that survey and as a result of it the Mayor has done 
two things: He has directed, first, that the study be continued and 
that we determine what would constitute a streamlined and reason- 
able set of rules to apply to motion picture production in the City of 
New York. 

That is well on its way, and I hope and expect that within the 
next month or two at the most, we shall have a simplified code which 
can be readily understood and easily followed out by the industry. 

We have not been content simply to wait for the passage of that 
time while this study and survey are being made. Late in August 
the Mayor established a Co-ordinating Office. I can say this to you 
now and if there be any inaccuracy in my statement I see enough of 
the people in New York here who have participated in the various 
conferences and who can tell you the respects in which my state- 
ments may be inaccurate. I say they are not. 

Since late August, on the basis of the only complaint made by the 
industry and we invited complaints in every respect there has not 
been one picture company that has come to New York and sought to 
produce that has made a complaint with reference to the service that 
it is getting. Many of the people do not realize that this is a city of 
close to 8,000,000 people. It is a city where we have dozens and 
dozens of different departments and necessarily must have those 

Our Police Department naturally must stand on its own. 

6 MAGTJIRE January 

We have a Department of Housing and Buildings that is concerned 
with structures. 

We have a Department of Public Works that operates most of our 
public buildings and our bridges. 

We have a Department of Water Supply, Gas, and Electricity 
whose responsibility includes that of insuring proper wiring and 
servicing with reference to electricity. 

We have a Department of Marine and Navigation that has juris- 
diction over our docks and our ferries: 

We have as a separate body the Triborough Bridge Authority 
which operates our tunnels and certain bridges. The Port Authority 
control many of our bridges. 

We have the Board of Transportation for our subways. 

Now, I admit that for a production manager to come to New 
York and try to break through that maze of jurisdictions would be a 
pretty difficult and trying task. It was because of their efforts in 
that direction, because of their lack of knowledge of the jurisdiction 
of the respective departments, that there had been confusion, there 
had been delay, and there had been red tape. This Co-ordinating 
Office has been set up. It is no longer necessary for the production 
manager to know the jurisdiction of the different departments. 

At this time any production manager who wants to take scenes in 
the City of New York, has only to contact directly the office of the 
Co-ordinator. If in certain situations permits are required, those 
permits are procured for the unit by that central office. 

We have worked the thing down to the point now where only a 
very short time is necessary to obtain clearance. As an example of 
it, one morning a major motion picture company called; they wanted 
to take certain pictures. It was just a telephone call. The thing 
was arranged for them within a half hour. They were taking scenes 
in connection with other pictures over the course of the past few 
weeks in New York. Those arrangements were made over the 
telephone, without the need of any permits, and when they got to 
the location of the scenes the police were there ready to protect 
them and afford them all that they required. 

We can do that and are doing it, and I ask you to inquire of any 
company that has been shooting in the City of New York in the 
past two months, if they had a single cause for complaint. If they 
have, then the proper and fair thing for them to do is to state the 
complaint to us, because we are not sensitive and it is our only 


purpose and design to cure the mistakes we have been making in the 

On the other hand, we do need some co-operation from the industry. 
You know, a director cannot come into New York with the idea of 
making thirty or forty exterior scenes, come in, let us say, on a 
Saturday, expect to pick out his locations and scenes and then want to 
start shooting on Monday morning, because even he does not really 
know what scenes he wants after he just gives it a superficial study. 
I think that the industry cannot only save us trouble and we are 
not bothered about it, we are willing to go through trouble but can 
save money for the industry itself, if it will only do a little more and 
better planning in selecting its locations. 

We ask for the co-operation of the industry. I say this: In the 
meetings that I have had with the industry representatives, I have 
received co-operation. The industry designated a committee of five 
that has been sitting with the various Commissioners and heads of 
different City Departments, telling those heads of the departments 
the needs of the industry. Out of that, as I said before, will come 
this very simplified and streamlined code. Out of this also will come 
a long-range and central co-ordinating office which will continue along 
the same lines that we have been following for the last two months. 

We are going to say this to the industry in behalf of the Mayor 
and in behalf of the City Government: We think we have much, that 
you need. We are only too happy to try to understand your prob- 
lems and we want you to call upon us in any respect and on any thing, 
to help us study and solve your problems and in return we ask for a, 
fair, reasonable share of the industry. 

New One-Strip Color-Separation 
Film in Motion Picture Production* 


Summary A description is given of procedures to be used with the 
new Ansco Film Type 155 which is designed for making color-separation 
negatives. Equal gammas are obtained for the red, green, and blue filter 
exposures with the same developing time, making it possible to obtain the 
black-and-white separations as successive frames on a single strip of film 
and thus obviate much of the difficulty of registration. By varying the 
developing time or developer formula, it is possible to change the gamma 
over a range of 0.5 to 2.0 to suit the purpose for which the separations are 
intended, while still maintaining equal gradations for the different filter 

The following are some of the applications for the film which are de- 
scribed: (1) to provide duplicates of Ansco Color originals for protection 
or (2) foreign release, (3) for special-effects and process photography in 
conjunction with Ansco Color motion picture films, and (4) for direct photog- 
raphy of animated cartoons which are to be printed in Ansco Color. 

THE USE OF monopack color films such as Ansco Color Types 735 
and 732 for the original exposure and the release printing stock in 
the production of motion pictures, poses certain problems in providing 
the intermediate duplicates or masters which are necessary for pro- 
tection of the original, for foreign release, or special effects. Methods 
for making such duplicates using Ansco Color Type 132 have been 
described by Duerr and Harsh. 1 The present paper describes an- 
other method for making intermediate duplicates, utilizing a new 
black-and-white film designed especially for color separations. 
The specific problem in motion picture color photography with 
monopack materials is the loss of color saturation when it is necessary 
to make second, third, or fourth generation duplicates to arrive at a 
release print as is often the case in black-and-white motion picture 
practice. Current use of monopack color processes such as Ansco 
Color has proved that a direct print from a color original gives color 
reproduction of satisfactory quality. The difficulty in making more 
than a first generation print is due to the absorption characteristics of 
the image dyes. Fig. 1 shows the spectrophotometric curves for the 
image dyes of Ansco Color Film in the proper proportion to give a gray 
density of one. 

* Presented October 21, 1946, at the SMPE Convention in Hollywood. 



To achieve accurate color reproduction, the intermediate duplicates 
should have yellow, magenta, and cyan images that are the exact 
counterpart of those in the original. A glance at the absorption 
curves of the yellow, magenta, and cyan dyes shows that the cyan ab- 
sorbs appreciable amounts of blue and green and that the magenta 
absorbs appreciable amounts of blue. These absorptions are unde- 
sirable and to the extent to which they take place they contribute to 

}n millimicrons 
FIG. 1 Spectrophotometric curves of dyes in Ansco Color Type 735. 

color degradation and poor color reproduction. From these curves 
it becomes evident that the blue component of the printing light will 
not only copy the yellow image in the transparency but also the ma- 
genta and cyan. Hence, the yellow image in a second generation 
print is no longer a true representation of the yellow in the original and 
the same is true for the magenta. If this is to be used for another in- 
termediate from which release prints are to be made, further degrada- 
tion of color will take place. The result is a loss of color brilliance 
which may not be acceptable to critical audiences. The difficulty is 
obviated if the intermediate duplicates are made in the form of black- 
and-white separations. By the use of sharp cutting niters it is pos- 
sible to obtain accurate black-and-white records of the red, green, and 
blue densities as they are present in the original. These negatives 




after being converted to black-and-white positives can be printed with 
identical or similar tricolor filters onto Ansco Color Type 732. 
The idea of making separation negatives from monopack color orig- 
inals is not new and has been applied in imbibition and other color 
printing processes for many years. However, a black-and-white film 
which is designed especially for this purpose has not been generally 
available and it has been found desirable to develop a new type of 
film to meet this requirement. The new film is tentatively designated 
as Ansco One-Strip Color-Separation Film, Type 155. 

/Tnsco One-ofcrip Separation 
film , Tuoe 155 


FIG. 2 Characteristic curves for Type 155. 

Accurate registration of separation negatives is essential in motion 
pictures. The ideal solution would be a film base material with high 
dimensional stability, but such a base material which is suitable for 
photographic use has not yet been realized. This problem is solved 
in the new film by making the separations as successive frames on the 
same 35-mm strip so that any shrinkage or other changes or varia- 
tions in physical properties of the film with handling and aging will re- 
main the same for all three filter exposures. Hence, the term "one- 
strip color-separation film 1 '. 

Equally important is the need for balance in the gradations of the 
three separations. In the past this has been achieved by giving the 




different filter exposures differential development. Since the three 
separations are on the same strip of film in the new material it is essen- 
tial that the same effective contrast for the blue, green, and red filter 
exposures be obtained when developed for the same length of time. 
This is the important feature of Type 155. The lower set of curves in 
Fig. 2 shows the characteristics for the red, green, and blue exposures 
when developed to a gamma of approximately 0.65. This is the de- 
sired value for separations from Ansco 735 Type originals. Where it 
is desirable to include the technique of color correction by masking, 
the separation film should be developed to an appreciably higher con- 
trast. Therefore, the material must have a wide latitude of gradation. 
The upper set of curves in Fig. 2 shows the characteristics for a higher 

FIG. 3 Spectral Sensitivity of Type 155. 

contrast and it is noticed that the curves still retain the same equal 
gammas with different filter exposures as obtained with the shorter 
developing time. The normal density differentiation of a Type 735 
original is approximately 1.6. It is seen that this range is adequately 
covered in the straight-line portion of the H and D curves. 

Another feature of this new film is the sensitization which is ex- 
tended farther into the red than a normal panchromatic film. The 
spectral response of Type 155 is shown in Fig. 3. The reason for 
this is apparent when you refer to the spectrophotometric curves of 
Fig. 1. You will note that the cyan-dye image has a maximum 
absorption at 680 millimicrons whicJi corresponds to the maximum of 
the red sensitivity of the film. This enables one to use an extremely 
sharp cutting filter such as the Wratten 70, the cutoff of which is well 
beyond the sensitivity range of a normal panchromatic film. The 




use of the extended red sensitization in conjunction with the 70 filter 
gives a red filter separation that is for all practical purposes perfect, 
thereby achieving a considerable increase in saturation especially for 
the reds and those colors in which red plays a part. 

The following will describe briefly the application of the film in the 
production of Ansco Color motion pictures. Fig. 4 shows graphically 
the steps involved. The scene is photographed on Type 735 film. 
This is then copied on Type 155 film using a printer equipped with 

FIG. 4 Graphic representation of steps involved in using Type 155. 

registration pins and capable of skip-frame printing. It will also be 
advantageous if the printer has a synchronized filter wheel so that the 
red, green, and blue filter exposures can be made on successive frames 
in one printing operation. However, the latter is not essential and 
the black-and-white film can be printed three times and still obtain the 
images successively by techniques well known in optical printing. At 
this stage, fades, lap dissolves, and other special effects can be included. 
The type 155 film is then developed to a gamma of approximately 
0.5 to 0.6 in a buffered borax developer of the type used for vari- 
able-density sound film. The resultant film now is a conformed mass 
ter containing all of the effects and with the color records as succesive- 
black-and-white frames. It will serve as protection against damage 


to the original color transparency since it is a good permanent record. 
The latter point is an important one since present-day color originals, 
if not stored under the proper conditions, may be subject to fading. 

To convert the separation negatives to color prints they are first 
printed on standard black-and-white duplicating positive film on the 
same optical equipment as used for making the negatives. That is, 
the one-strip separation negatives are now converted into separation 
positives using three separate films. The final step is to print the 
separation positives onto the Type 732 Ansco Color printing film. 
This can be done in a standard contact step printer equipped with re- 
gistration pins by printing the Type 732 film three times, each time 
using the appropriate separation positive and filter. It is also pos- 
sible to make the black-and-white positives by contact from the nega- 
tives. In this case, release printing would have to be made on a skip- 
frame printer. In either case, the result is a release print which is 
equal to a direct print from the original in color reproduction. 

Because of its unique feature of maintaining the same gamma for all 
three filter exposures over a wide range of gammas, Type 155 can also 
be applied to the direct photography of animated pictures or used for 
background projection and process photography. Those skilled in 
motion picture methods will immediately recognize other important 
uses of this new film in the production of color motion pictures. 


(1) H. H. Duerr and H. C. Harsh, "Ansco Color for Professional Motion 
Pictures," Jour. Soc. Mot. Pict. Eng., vol. 46, pp. 357-368; May, 1946. 


MB. S. P. SOLOW: Could you tell us to what extent different colors produce 
different gammas on ordinary film? 

MR. H. C. HARSH: Usually the blue separation is softer than the others, and 
requires about two minutes more development time to bring it into equal grada- 
tion. They vary on the red and green. One tune the green might be a little 
different from the red and vice versa, depending on the film. 

MR. HERBERT GRIFFIN: Suppose your color original does not have the same 
red, green, and blue printing contrast, then how do you proceed? 

MR. HARSH: This film was designed especially for use with Ansco Color Type 
735 which gives a balanced print on Type 732 printing film. We are using it only 
as an intermediate step. We want to retain the same gamma relation in our black- 
and-white dupes as we have in making a direct print. Ordinarily, in using a black- 
and-white separation film, you would proceed from a well-balanced original. In 
the case of a faulty original the development times for the black-and-white positive 
could be varied for correction without interfering with the one-strip negative. 

A New Variable- Area Recorder 
Optical System* 




Summary A new variable-area recording optical system is announced 
which incorporates refinements and improvements in design and arrange- 
ment that make for better performance and more convenient operation, 
maintenance, and servicing. Optical features include improvements in aper- 
ture condenser, aperture, and intermediate objective lens designs; in design 
and mounting of slit; in mounting of filter; in ground-noise-reduction shutter 
and phototube monitor; in design and mounting of monitoring optics and 
monitoring screen. The system incorporates features enabling the operator 
to record a negative or positive track at will; it utilizes a new low-distortion 
galvanometer previously announced before this Society. It has been ex- 
pressly designed as a component part of a new de luxe recording machine, 
RCA Type PR-31, also previously announced before this Society. 


FEATURES THAT have been under development by the Radio Cor- 
poration of America for nearly twenty years, as well as a number 
of recently developed improvements, have been incorporated into a 
variable-area recorder optical system of entirely new design. Numer- 
ous papers by Kreuzer, 1 Dimmick, 2 Hasbrouck, Baker and Batsel, 3 
Kellogg, 4 and others have described the principles, construction, and 
use of the area optical system during the course of its development. 
The new optical system is especially designed to accompany the Type 
PR-31 de luxe 35-mm recorder (Fig. 1) recently described before the 
Society. 5 The optical system is shown mounted in the recorder in 
Fig. 2. Basic features of the variable-area optical system, such as in- 
candescent lamp, electromagnetically driven mirror, and the shaped 
aperture whose image is moved across the slit by the mirror, are re- 
tained. Improvements in component parts and assemblies, and re- 
finements in the arrangement and design of the general layout and 
accessory equipment, enhance performance and operating conve- 
nience, and make for economy in maintenance and servicing. 

* Presented April 24, 1947, at the SMPE Convention in Chicago. 



A. General Arrangement of the Optical System 

. As illustrated in Fig. 3, the general layout is roughly in the form of 
an L with the illuminating branch at right angles to the modulating 
branch. For reasons of geometry the two branches have been re- 
tained effectively at 30 degrees to each other, but the prism E folds 
the illuminating branch so that the over-all system has the general 
shape of an L. This arrangement permits an effective increase in the 

Fig. 1 View of Type PR-31 recorder, showing visual monitoring 
screen and light-meter plunger. 

distance from lamp A to mirror /, of well over an inch without inter- 
ference between the optical and recorder assemblies. It increases 
certain optical clearances that make possible new features to be de- 
scribed later. The new layout makes the lamp adjustments more 
accessible, and improves thermal isolation of the lamp from the modu- 
lating branch of the system. 

B. New Features of Arrangement and Design 

The new optical system has the following specific features, some of 
which are consequent upon the new general arrangement described 




above. Except where noted, they are all standard equipment. 

1. Prefocused exposure lamp, adjustably mounted and thermally 
insulated from main base plate. 

2. Two-element aperture condenser. 

3. Compensated 6 apertures with azimuth adjustable by opposing 

4. Air-spaced intermediate objective lens. 

5. Low-distortion galvanometer 7 with large protective 

6. Large diameter slit condenser. 

7. Slit of entirely new design 
with azimuth adjustable by op- 
posing screws. 

8. Single-vane, fully ad- 
justable ground-noise-reduction 
shutter 8 for class A push-pull and 
duplex recording. (Auxiliary 
equipment, not standard.) 

9. Reversible ultraviolet 
filter assembly, easily removable 
for cleaning. 

10. Isolated focus adjust- 
ment for objective lens. 

11. Top-mounted phototube 
monitoring system 9 with photo- 
tube in upright position to the 
rear. (Accessory equipment.) 

12. Fixed optics for monitor- 
ing galvanometer, ground-noise- 
reduction shutter and lamp fila- 
ment visually, by rear-screen, 

line-of-sight projection, with monitoring screen mounted to the operat- 
ing side of the system (Fig. 1). 

13. Thumb-actuated, safety-locked light-meter control. 

14. Aperture of entirely new design for recording positive or nega- 
tive bilateral tracks at will. 

15. Standard equipment provides for recording new double bilat- 
eral tracks designed to reproduce equally well in standard or push- 
pull sound heads. 

16. Bias-type ground-noise reduction for bilateral recording. 

Fig. 2 Optical-system assembly 
mounted in Type PR-31 recorder. 
Phototube monitor assembly just 
visible at A behind visual monitor 




17. Optical system adjustable to record at standard or other dis- 
tances from either edge of film. 

18. Unit subassembly construction employed throughout. 

19. All objective housing assemblies premachined to mount 
phototube monitoring and ground-noise-reduction shutter assem- 
blies when required. 

20. All lenses and prisms coated to reduce reflection, except in 
visual monitoring and light-meter systems. 


A Lamp j 

B Condenser lens -^ H 
C Condenser lens 
D Aperture 
E Right angle prism 
F Intermediate objective lens 
H Window galvanometer 
J Mirror galvanometer 
K Slit condenser lens 
L Slit 
M Filter 
N Objective lens 

EY Prism 
FY Plane glass plate 
HY Cylindrical lens 
JY Aperture 
KY Cylindrical lens (2) 
LY Plane glass plate 
MY Phototube 

STAN DBY -'\_ } | AX 


Fig. 3 Schematic plan view of the optical system. 


A. Component Optical Systems 

The new system includes the following seven distinct component 
optical and electromagnetic systems; all are standard equipment ex- 
cept as indicated : 

L The Basic Optical System: This may be traced by referring to 
the schematic plan view of Fig. 3, and following the legend "Basic 
Optics" in the order of progression of the light from A through N. 




2. The Modulation Monitoring Optical System: . This may be traced 
by referring to the schematic front and side elevation views of Figs. 4 
and 5, respectively, and following the legends "Modulation Monitor- 
ing" in the order of progression of the light from AX through FX. 

3. The Filament Monitoring Optical System: This may be traced 
by referring to the schematic side elevation and plan views of Fig. 5, 
and following the legend "Filament Monitoring" in the order of pro- 
gression of the light from JX through FX. 

4. Phototube Monitoring Optical System (Accessory Equipment): 9 
This may be traced by referring to the schematic plan and front 

AX Spherical condenser 
BX Right-angle prism 
CX Spherical .projection lens 
DX Trapezoid 
EX Mirror 
FX Screen 



A Y Selective reflector 
BY Cylindrical lens 
BY Aperture 
DY Cylindrical lens 
EY Prism 

AZ Piano-spherical lens 
BZ Right-angle prism 
CZ Window 
DZ Light cell 

Fig. 4 Schematic front elevation of the optical system. 

elevation views of Figs. 4 and 3, respectively, and following the 
legends "Phototube Monitoring" in the order of progression of the 
light from AY through EY, and from EY through MY. 

5. Light-Meter Optical System: This may be traced by referring to 
the schematic front elevation view of Fig. 4, and following the legend 
"Light-Meter Optics" in the order of progression of the light from AZ 
through DZ. 

6. Low-distortion Galvanometer: 1 This is a vibrating mirror type 
of light modulator, the mirror being shown at J in Fig. 3. The motor 
that drives the mirror is of the balanced-armature type and has un- 
usually low distortion. 




7. Single-Vane Ground-Noise-Reduction Shutter (Auxiliary Equip- 
ment) : This is a moving-armature type of motor 3 moving a suitably 
shaped metal vane up and down very close to slit 8 L of Fig. 4, and be- 
tween it and lens AX. A description of its optical perform- 
ance will be given in II,B,7 below. 

B. Features of the Component Optical Systems 

1. Basic Optical System: In this optical system (Fig. 3) the fila- 
ment of lamp A is imaged by condensers B and C and lens F, upon 
galvanometer mirror J. The filament image fills this mirror. The 

PLAN view 

AX Spherical condenser 
BX Right-angle prism 
CX Spherical projection lens 
LX Trapezoid prism 
EX Mirror 
FX Screen 

JX Mirror 
KX Projection lens 
LX Aperture 
MX Mirror 
NX Mirror 
RX Window 
CX Screen 

Fig. 5 Schematic side elevation and partial plan view of the optical system. 

aperture D is imaged by lenses F and K upon slit L, where rotary vi- 
bration of J makes this image move across the slit to vary the length 
of its illuminated portions. Lens K produces an image of mirror J 
in objective lens N, and lens N images the slit L upon the sensitive 
film emulsion. Prism E folds the optical system into the L shape 
discussed above; window H protects the galvonometer motor from 
dust ; and filter M controls the spectral distribution of the light that 
finally exposes the film. 

The arrangement is essentially like that used in former systems of 


this type, but includes a number of improvements. The double 
condenser B and C is especially designed to minimize .spherical 
aberration in the image of the filament at the mirror J. 
The effect of this is to improve uniformity of illumination in the aper- 
ture image that illuminates the slit. The lens at F is an air-spaced 
crown and flint pair designed to flatten the aperture image at the slit 
and is an improvement upon the former cemented doublet lens in this 
respect. Lens F has been specifically designed for this application 
and full account has been taken of the effects of lens K upon the 
image. Lens K has been increased in size for easier cleaning. 

The slit L is of entirely new design, and replaces the fabricated slit 
formerly used. The new slit is formed on glass by a special technique 
and embodies a number of desirable qualites that constitute an im- 
provement over the old mechanical slits as follows: 

(a) The slit is between glass plates where it cannot accumulate 
dirt. It can be readily cleaned by methods suitable for glass surfaces 
without damage to the slit. 

(6) The slit edges are smooth, straight, and parallel, and its width 
is precisely controllable in manufacture. Its width cannot change 
after the slit is made. 

(c) The layer forming the slit is only a few light wavelengths in 
thickness. It produces no vignetting as in mechanical slits where the 
metal edges forming the slit had to be about 0.003 inch thick to be 
practical. (In the mechanical slit, which was 0.0018 inch wide, the 
thickness of the metal edges was nearly twice the slit width.) 

The slit azimuth is readily adjusted and secured by a pair of oppos- 
ing screws. 

The lamp A, in prefocused base with curved filament rated at 10.5 
volts 7.8 amperes, is fully adjustable for location and height. 

The apertures designed to be located at D are compensated 6 to neu- 
tralize the rotation effect in the aperture image, that results from the 
vibration axis of the mirror / making an oblique angle with the pro- 
jection axis. This is accomplished by appropriately computing the 
angles of the cutting edges of the apertures, with the obliquity of the 
mirror J taken into account. Also, in each aperture there is at least 
one edge that is imaged approximately parallel to the slit. These 
edges are specially oriented with respect to the cutting edges so that, 
when their images are brought into coincidence and parallelism with 
the slit, the associated aperture is automatically in approximately 
the correct azimuth for proper operation of the system. 


The filter M is readily removable for cleaning or replacement with- 
out disturbance to any adjustments, and the objective lens N moves 
independently of all other adjustments for focusing purposes. 

Objective N produces a track of standard width, and a special ob- 
jective to make a track that conforms to the wide standard is in 
course of design. 

2. Modulation Monitoring Optical System: In this optical system 
(Figs. 4 and 5) a portion of the light arriving from the mirror / at the 
slit L passes through a window in the slit and enters the lens AX. It 
is then reflected downward by prism BX to lens CX in which there is 
formed an image of mirror /. The light is then doubly reflected by 
prism DX to mirror EX and thence to the screen FX where lens CX 
produces an image of the window in slit L. The monitoring aperture 
in D (Fig. 3) is imaged in this window, and the noise-reduction shut- 
ter, when used, is in a plane very close to the window. Thus motions 
of both mirror J and the shutter vane can be registered upon the moni- 
toring screen. The precise operation of the visual monitoring light 
beam will be explained in connection with the description of the 
ground-noise-reduction shutter vane in II,B,7, below, and also in 
connection with the description of the action of the system when re- 
cording bilateral negatives and positives, in II,C,4, below. 

All optical elements in the modulation monitoring optical system 
are fixed in position, and the projection lens CX is provided with a 
screw-driver adjustment for focusing. 

The screen FX is translucent and the image projected upon it from 
the rear. It is tilted back at an angle of 30 degrees to the vertical to 
provide for more comfortable viewing; the light is projected upon the 
screen normally and in the line of vision to provide maximum ob- 
served image brightness for this type of projection, and to avoid key- 
stone in the images. Built-in straight edges for drawing limit lines, 
and colored overmodulation indicators are provided. The. screen de- 
flections are five times as great as the deflections of the aperture image 
in the plane of the slit. 

8. Filament Monitoring Optical System: In this optical system 
(Fig. 5) light is received by mirror JX from the concave side of the 
curved filament of lairip A, and reflected to lens KX which is provided 
with a small aperture LX. Thence it passes to mirrors MX and NX 
which reflect it to the back of screen FX where it is incident normally 
to the screen surface in the line of vision. The lens KX produces an 
image of the filament upon the screen. The axis of the filament 


appears vertical on the screen and there is no keystoning. The image 
is formed at a magnification of 3.75 X for comfortable 'vie wing. 

4. Phototube Monitoring Optical System: In this optical 
system (Figs. 3 and 4) a selective or dichroic reflector 9 A Y between the 
slit L and objective N receives the light from the slit, reflecting the 
red vertically for monitoring purposes and transmitting the violet and 
ultraviolet to objective N and the film to expose the sound track. 
From reflector AY the red light passes through cylindrical lenses BY 
and DY which image the slit upon the beam-splitting cylinders KY 
after passage through prism EY. The light from one half of the slit is 
directed by lenses HY and one of the lenses KY to an image of the gal- 
vanometer mirror on one cathode of the RCA-920 push-pull photo- 
tube MY. Light from the other half of the slit is similarly directed to 
the other cathode. An appropriate switching arrangement in the cir- 
cuit associated with the phototube permits audible monitoring of 
standard or push-pull recordings with the same monitoring optical 

5. Light-Meter Optical System: In this optical system, Fig. 4, a 
simple lens AZ is cemented to the right-angled prism BZ; the com- 
bination converges and directs all the light from galvanometer mirror 
J upon photovoltaic cell DZ in the base of the optical system. The 
cell is protected by the dust window CZ. Except when metering the 
light, the lens and prism assembly is drawn aside by a spring to a 
stand-by position in which it is safety-locked to avoid accidental in- 
terruption of a recording by inadvertently pushing the light-meter 
optics into their operating position. The light-meter optics and actu- 
ating arm are mounted integral with the visual monitoring optical 
system. The actuating button is in the recorder housing and an ad- 
justable member makes the meter operable with the optical system in 
position to record at standard or other distances from either edge of 
the film. 

6. Galvanometer: The galvanometer is of new design. It has un- 
usually low distortion, 7 and is equipped with a 1 /s- X Vio-inch rec- 
tangular mirror and large dust window for easy cleaning. A bias coil 
is provided for ground-noise reduction when bilateral tracks are to be 

7. Single-Vane Ground-Noise-Reduction Shutter: 8 This unit is a 
necessary auxiliary to the recording of duplex and class A push-pull 
tracks for the production of which the bias-type ground-noise-re- 
duction system is not applicable. Its action from the optical 




standpoint is readily understood by referring to Fig. 6, which, 
from the galvanometer mirror, is a view of the slit S and 
monitoring window W, showing a superimposed image A of the 
class A push-pull aperture. It also shows in phantom the out- 
lines of the ground-noise-reduction shutter vane V which is just be- 
hind the slit. M is the image of the monitoring aperture associated 
with the class A push-pull aperture. In action, images A and vane V 
move up and down transverse to the slit as indicated by the two-headed 
arrow. Two edges of the opening in the shutter vane cross the 
slit at points equally spaced from its center and between which the 
vane does not cover the slit. The cutting edges of the images A also 
cross the slit at points equally spaced from its center; they are de- 
signed to intercept the slit at all points when moved up and down, 

Fig. 6 Action of the single-vane 
ground-noise-reduction shutter. 





Fig. 7 Appearance of visual 
monitor when ground-noise-reduc- 
tion shutter is employed. 

save a neutral portion or septum at its center. The images A are 
shown in their stand-by position with cutting edges intercepting the 
slit at points midway between septum and ends. The vane V is raised 
to the position shown, by application of direct current to its motor, 3 
until the portions B of the slit covered by images A and also uncov- 
ered by the vane V are sufficiently long to trace in the track bias lines 
that have the required width. As voice currents are applied to move 
images A up and down, the current holding vane V in this top posi- 
tion is automatically reduced, and the opening assumes a lower posi- 
tion, as it opens the slit farther to accommodate the excursions of 
images A. When the voice currents cease, the vane V rises again and 
restores the narrow bias lines to the track to minimize ground noise. 
A portion of the image M, as shown in Fig. 6 , passes through win- 
dow W in the slit plate, and of this a further small portion is inter- 
cepted by tab T appended to shutter vane V. The light that passes 
through W and is not intercepted by T reaches the monitor screen as 


the image SM of Fig. 7, where S is the image of the lower edge of the 
tab T and M that of the image M of Fig. 6. Modulation and dis- 
placements of the shutter are indicated by independant motions of the 
ends M and S, respectively, of the image as shown in Fig. 7. 

C. Types of System Operation 

Fig. 8 illustrates schematically the various types of recording aper- 
tures and slits that may be employed with the new optical system. 
Other types may also be used for producing special kinds of sound 
tracks, but those illustrated are designed to produce the tracks most 
commonly used. 


COMB.NAT.ON APERTURE-PC^* V-^^fl ~ ^-= Jf sTpT^ 

Fig. 8 Assortment of slits and apertures for recording negative 
and positive tracks. 

1. Class A Push-Pull Negative: For this type of operation, the 
compensated 6 class A aperture and single slit of Fig. 8 are used. The 
noise-reduction shutter is required as auxiliary equipment, and the 
appearance of the monitoring beam on the screen is as shown in Fig. 
7. The track produced is well known and has been discussed in past 
issues of the JOURNAL. 10 Its commercial application is of long 

2. Duplex Negative: For this type of operation, the compensated 
duplex aperture and single slit of Fig. 8 are used. The noise-reduction 
shutter is also required, and the visual monitoring image has the same 




appearance and action as in class A push-pull operation (Fig. 7). 
There are many references to this type of track in the literature, 3 ' 10 
and it has long been in commercial use. 

8. Class B Push-Pull Negative: For this type of operation, the 
compensated class B aperture and single slit of Fig. 8 are used. No 
ground-noise-reduction equipment whatsoever is required. The vis- 
ual monitor indication is essentially the same as described for the 
type of operation to be discussed in the next subsection. This type 
of operation has been described in detail and has been in commercial 
use for many years. 11 ' 12 


Fig. 9 Action of the double-W aperture and combination 
slit, in the production of both negative and positive master 
double bilateral tracks. 

4. Double Bilateral Negative or Positive Master: In this type of 
operation, a special compensated combination aperture known as 
double-W and combination slit are used. These are illustrated sche- 
matically in Fig. 8. The drawing of Fig. 9 shows in detail how this 
aperture and slit co-operate to produce a negative or positive track at 
the will of the recordist. The shaded areas A represent the image of 
the double-W aperture, and areas P and N the images of the two moni- 
toring apertures associated therewith. S is the recording slit in the 
plane of the aperture image, and W is the window in the slit plate 


through which the monitoring beam passes to the monitoring optical 
system and screen. The two auxiliary slits X below the recording 
slit serve to expose the track to standard printed area width 13 when 
recording a positive master track. 

In recording a negative track, the image A and slits S and X bear 
the relation illustrated in (a) of Fig. 9. The negative track appears 
as shown directly below, where the shaded areas correspond to the 
dense parts of the track. During modulation, the lower edge of A 
may drop to, and vibrate vertically about, mean positions as low as 
the limit indicated by the phantom line. This mean position is con- 
trolled by the bias current in the galvanometer 7 for noise-reduction 

In recording a positive master track the image A and slits S and 
X bear the relation illustrated in (6) of the figure. The positive mas- 
ter track appears as shown directly below, where the shaded areas 

correspond to the dense parts of 


80% MODULATION AND ovtu. the track. During modulation the 

lJj!L! u PP er ed S e of A ma y dr P to > and 

vibrate vertically about, mean po- 

^7% sitions as low as the limit indicated 

by the phantom line. This mean 

position is controlled by the bias 
Fig. 10 Appearance of visual 

monitor when bias ground-noise current in the galvanometer for 
reduction is employed with double- noise-reduction purposes. 
W aperture. i j 

The track produced is in two 

identical parts as indicated in Fig. 9, each being of the bilateral type, 14 
hence the name double bilateral. The advantage of the double over 
the old single bilateral track is that it can be reproduced in push-pull 
type reproducers 11 without incurring distortion at low levels. In the 
case of the single bilateral track, distortion could be caused by the 
track center, where low modulations occur, riding a little off the 
center of the septum of the beam splitter. In the case of the double 
bilateral track, no interference between the track and the septum of 
the beam splitter can occur, except at full modulation, where its 
effect would. not be so serious. The new track thus minimizes effects 
of track mislocation in reproduction. 

The design of the combination aperture and slit allows 200 per cent 
amplitude to be impressed on the galvanometer before modulation of 
the auxiliary slits X will occur. This applies whether a negative or 
positive master is being recorded. 


When negatives are being recorded the monitoring beam TV of Fig. 
9 is imaged on the screen, and when positive masters are being re- 
corded the beam P is so imaged. In Fig. 10, the solid-hatched rec- 
tangle represents the beam on the monitoring screen when negatives 
are to be recorded. The monitoring apertures are staggered so that 
when positive masters are recorded, the beam falls lower on the screen 
to the position indicated by the dotted crosshatching. The end B of 
the rectangles indicates the ground-noise-reduction bias adjustment 
under stand-by conditions, and the end M moves as shown when 
modulated 100 and 200 per cent. During modulation the rectangle 
BM may move to the right, and vibrate horizontally about mean posi- 
tions to the right of that shown. The amount of this displacement 
of the mean position is indicated by the range labeled "Bias Deflec- 
tion". This action is controlled by the bias current in the galva- 
nometer 6 for noise-reduction purposes. 

5. Standard Equipment: The combination (or double- W) aperture 
is supplied with the optical system as standard equipment in response 
to a growing interest in directly recorded positive sound tracks. 
Such tracks 8 have been used in the recording of high-quality masters 
that are then re-recorded to disks without intervening steps involving 
quality losses in sound printers. These tracks are also used as black- 
and-white masters for the production of dye tracks on color prints 
that are produced by reversal. 15 It has been found that better color- 
tracks result by working from a directly recorded positive master than 
from a positive master printed from an original negative. 

In addition to a combination aperture and slit for negative or posi- 
tive master recording, standard equipment also includes coated lenses 
and prisms throughout, except in the visual monitoring and light- 
meter systems. 

6. Wide-Track Recording: A special objective lens is in course of 
design. It is interchangeable with lens N of Fig. 3, and will render the 
optical system capable of recording wide sound tracks in accordance 
with Academy Research Council Specification RC-5001. 


Recent studies have shown that a de luxe recording optical system 
must be highly flexible if it is to fulfill the requirements of the present- 
day art. As shown in Fig. 2, the general arrangement and design 
consist of a common base supporting several subassemblies, which 




permits simplification of manufacturing and flexibility of con- 
struction. The over-all design has been made to harmonize with the 
construction of the RCA Type PR-31 de luxe film recorder 5 and these 
two devices combine to provide a unit capable of producing sound- 
film records of extremely high quality. 

The design provides wide clearances for all component parts and the 
assembly is removably mounted on the recorder mechanism. When 

Fig. 11 Standard Type PR-31 recorder optical system, exploded into 
component subassemblies. 

mounted in the Type PR-31 recorder (Fig. 1) the optical system is ac- 
cessible for routine inspection through a wide hinged door, with com- 
plete accessibility afforded by easy removal of the entire optical sys- 
tem compartment housing, which is part of the recorder assembly. 
Lightweight materials have been chosen in its construction where- 
ever possible. All castings are made of an aluminum alloy heat- 
treated for maximum dimensional stability. Each part has been either 
anodized or nickel-plated to insure against corrosion and oxidation. 
In addition, an enamel finish has been applied to certain exposed sur- 
faces. This finish serves to enhance appearance, and harmonizes 


with the finish scheme of the Type PR-31 recorder. The selection of 
hardware permits the use of standard servicing tools, although the 
adjustable features have been carefully restricted to essential items. 

A. Component Assemblies 

Fig. 11 shows the various subassemblies detached from the main 
base, each such assembly being complete within itself. The various 
assemblies are described briefly as follows: 

1. Exposure Lamp Socket: This assembly (Fig. 11 A) permits the 
use of a curved filament prefocused lamp rated at 10.5 volts, 7.8 am- 
peres, and operating at approximately 3200 degrees Kelvin. It is 
mounted to a standard self -locking socket equipped with a pressure- 
release key for easy removal of exhausted or defective lamps. A mica- 
glass composition insulator is placed between the socket and the as- 
sembly base for thermal isolation. The entire assembly is oriented on 
the main base casting with adjustments provided in both horizontal 
and vertical planes. The horizontal adjustment is semifixed while the 
vertical adjustment is made accessible to the operator by means of a 
slotted shaft for com or screw-driver rotation. This rotation elevates 
the position of the lamp filament with respect to the optical axis. The 
adjustment is provided to compensate for variations in light center 
length tolerances for commercial lamps. A single-piece cover encloses 
the lamp yet provides adequate ventilation. Also attached to the 
socket assembly are the filament monitoring optics which indicate 
the position of the lamp filament relative to the optical axis as well 
as its configuration. In this assembly only three optical surfaces 
are exposed. 

2. Intermediate Objective Lens Assembly: Adjacent to the lamp- 
socket assembly is a bracket (Fig. 115) for housing the lamp conden- 
sers, recording apertures, 90-degree prism, and the intermediate ob- 
jective lens. This bracket is mounted to the main base as an indepen- 
dent unit which is oriented and doweled in place. It may be removed 
for interchanging with other types of intermediate systems without 
alteration to the other comporients of the over-all optical system. 
Lenses B and C and aperture D of Fig. 3 are assembled in a single de- 
mountable cell and mounted in the bracket nearest the lamp. Two 
opposing screws are provided in the bracket for independent aperture 
azimuth adjustment. The entire cell may be removed and replaced 
in the bracket without readjustment by means of dowel-pin position- 
ing. Opposite the condenser-aperture cell is located prism E of Fig. 


3, mounted in a fixed position and accessible by a single cover plate. 
Adjacent to this prism are the two components of the intermediate ob- 
jective lens F of Fig. 3 which are combined in a common cell and at- 
tached to the bracket in a fixed position. Neither the prism nor the 
objective lens requires adjustments beyond the factory alignment. 

3. Galvanometer Mounting: A yoke arrangement (Fig. 11C) sup- 
ports a low-distortion galvanometer. 7 All routine operational adjust- 
ments of the Type PR-31 recorder optical system are confined to this 
assembly. The adjustments for so-called "stand-by position" of the 
recording light beam are controlled by rotation of the bracket and gal- 
vanometer assembly about the point of intersection of the axis of the 
illuminating and modulating branches of the optical system. The 
yoke when attached to the main base plate (Fig. 1 IE) may be rotated 
on the vertical axis by adjustment of two opposing screws. The gal- 
vanometer tilt or adjustment on the horizontal axis for normal 50 per 
cent track exposure is accomplished by adjusting a large knurled 
screw extending from the rear of the bracket. The tilting screw 
likewise permits aligning the galvanometer for either negative or di- 
rect-positive recording by appropriately positioning the double-W re- 
cording aperture image superimposed upon the recording slit. Trans- 
fer from negative- to positive-type recording may be accomplished in 
matter of seconds. Spring tension is supplied to the tilting screw to in- 
sure stability of adjustment. 

4. Recording Slit, Monitoring, and Objective Lens Assembly: Fig. 
IID shows a housing for the slit condenser K, recording slit L, filter 
M, and final objective lens N (Fig. 3), as well as the various monitor- 
ing elements. This unit is mounted on the main base plate. Each 
of the aforementioned items of this assembly is an individual unit and 
will be described separately. Taken in order of the passage of light, 
the slit condenser lens K and the recording light slit L are mounted in 
a cell (Fig. HH) providing a dust-tight enclosure of the inner sur- 
faces of each element, while the exposed surfaces are made accessible 
for routine inspection. The slit condenser lens is held in the cell by a 
suitable spanner nut on the side nearest the galvanometer, while the 
slit, previously described in this paper, is retained on the opposite side 
of the cell. Slit azimuth adjustment is accomplished by means of 
opposing .screws while positive locking is obtained by suitable screws 
extending through an outer flange of the cell into the housing. The 
cell is doweled in place and may be removed for inspection without 
loss of azimuth. Located beyond this assembly is a plate providing 


a common mounting for all items of the visual monitoring system, 
except mirror EX and screen FX of Fig. 4. This assembly (Fig. 11F) 
may, by use of locating dowels, be readily removed and replaced with- 
out readjustment. Each optical element is positively positioned. 
When assembled in place, only one optical surface is exposed to open 
atmosphere. Also attached to this plate is the exposure-meter projec- 
tion assembly which, when ''triggered" into position, intercepts the 
recording light beam reflected from the galvanometer and projects the 
beam to a photovoltaic cell located in the base plate. The output of 
the photovoltaic cell is terminated at a meter located on the Type PR- 
31 recorder control panel. This device may be actuated through the 

Fig. 12 Visual monitoring screen assembly showing mechanical construction. 

closed recorder optical system compartment door by a nonlocking 
plunger mechanism (Fig. 1) or may be operated directly when the door 
is in open position. It is safety-locked in the nonoperating position 
to prevent accidental use during a recording operation. Towards the 
right from the monitoring assembly may be seen the ultraviolet filter 
and clear compensator M of Fig. 3, with both items mounted in a 
single holder (Fig. IIG). Selection of filter or compensator may be 
readily made by reversing the holder end for end on its supporting 
plate. To the extreme right of Fig. 1LD is the final objective lens bar- 
rel, focusing nut, and objective lens N of * Fig. 3. This assembly is 
mounted independently of all other optical elements and may be 
adjusted without disturbance to the remainder of the system. 




Calibrations on the focus-adjusting nut provide for easy and accurate 
setting of the objective lens. It is divided into 25 equal divisions pro- 
viding a 0.001-inch focal increment per division. The entire assembly 
is locked in place by a single pressure screw which does not disturb 
the lens position. A single cover plate totally encloses the housing, 
rendering it dust-tight. The phototube monitoring assembly, de- 
scribed above under II,B,4, replaces this cover plate when added as 
an accessory item. 

Fig. 13 Standard optical system assembly for the Type PR-31 

5. Visual Monitoring Screen: Fig. 12 shows the visual monitor 
screen assembly which is also attached to the objective housing as- 
sembly. The monitor screen receives the combined modulation and 
ground-noise-reduction monitor light beam as well as the projected 
image of the exposure-lamp filament. The assembly consists of a 
flashed opal-glass screen ground on the outer surface for ease of mark- 
ing, a pair of movable straight edges, a pair of movable color filters, 
and a mirror for reflecting the modulation monitor beam to the screen. 
Reference lines indicating "stand-by" and 100 per cent limits for both 
modulation, and bias indications are established on the screen by posi- 
tioning the straight edges to the respective positions of the light beam 


and then marking the screen with either pencil or pen. After calibrat- 
ing in this manner, the straight edges are moved to a positon of ap- 
proximately 200 per cent reference for both modulaton and bias. At 
this latter position, a colored filter is brought into position from the 
rear side of the screen for both references. When the system is in 
operation at a level in excess of 100 per cent for either modulation or 
bias, a contrasting color indicates the presence of overshooting. 
This arrangement affords the recordist an easily visible indication 
of excessive level that does not require critical observation. 

6. Over-all Assembly of Standard Features: Fig. 13 shows all the 
aforementioned items assembled in place. Attachment of the optical 

Fig. 14 Phototube monitoring optical system and transformer 


system to the recorder proper is accomplished with hold-down screws 
which permit the sound-track location on the film in the recorder to be 
controlled by two fine pitch lateral adjusting screws. A wide range 
of track positions is obtainable. The complete assembly weighs ap- 
proximately S l / z pounds and measures 8X8 X II 1 / 2 inches over all. 
The outer surfaces are finished light umber gray metaluster enamel 
with polished black accessories. 

B. Accessory and Auxiliary Equipment 

1 . Phototube Monitoring Assembly: A phototube monitoring device 
as shown in Fig. 14, and described in section II,B,4 above may be in- 
stalled as an accessory item. Mounting of this assembly is accom- 
plished by interchanging it with the objective housing cover plate, 




and without additional preparatory machining (Fig. 2). This as- 
sembly is also of unit construction except for the associated trans- 
former and control network to which it is coupled by a single cable. 
A selector switch on the transformer assembly mounting plate is lo- 
cated within the recorder optical system compartment, and permits 
operation as either "standard" or "push-pull," depending upon the 
type of sound track being made. 

2. Ground-Noise-Reduction Shutter Assembly: Fig. 15 shows the 
ground-noise-reduction shutter assembly. This is an auxiliary item 
required for recording class A push-pull or duplex tracks. This de- 
vice is new in construction but retains the electromagnetic motor 

(a) (ft) 

Fig. 15 Ground-noise-reduction shutter mechanism. 

mechanism of earlier shutters. 9 The new design embodies the follow- 
ing features : 

(a) A single vane insuring uniform masking of both ends of the 
slit; it is rigidly linked to a moving armature. 

(6) Independent adjustment of the shutter vane in three planes 
by means of an interlocked cross-slide assembly. 

(c) Moistureproof coils. 

(d) Low hysteresis iron for pole-piece construction. 

The entire unit is attached within the objective housing assembly 
and connected electrically to the over-all system by a single-pair con- 
ductor. All objective housing assemblies are premachined to mount 
shutters when required. Normal sensitivity of the shutter is in the 


order of 20 milliamperes direct current and may be operated from all 
RCA ground-noise-reduction amplifiers that operate on the principle 
of increased output with decreased input. The over-all linearity of 
the shutter-vane travel extends well beyond the maximum deflection 
required to mask the recording slit adequately. The moving mech- 
anism resonates at a frequency well above the highest that can appear 
in the output of the control amplifier. Optical monitoring of the 
shutter vane is accomplished by placing a small tab on one edge of the 
shutter vane to intercept a portion of the monitor light beam (section 
II, B, 7). No change in monitoring optics is required when install- 
ing the shutter assembly in the standard optical system. The photo- 
tube monitor can also be used with systems employing this shutter, 
without additional modifications. 

8. Wide-Track Recording Objective Lens Assembly: The wide-track 
objective lens assembly, which is in course of design, will be mechani- 
cally interchangeable with the lens that produces the normal or stand- 
ard track as defined by ASA Z22.40-1946. 


The RCA variable-area optical system has undergone a long period 
of development, during which many changes in both principle and de- 
tail have steadily increased flexibility and quality of performance, 
with little change in basic form. Oftentimes improved features have 
had to take the form of attachments that functioned well, but were 
at a disadvantage from the standpoint of appearance, location, or 
operating convenience, because they had been added to a system not 
originally designed for them. The optical system described here com- 
bines previously established features and quality performance, with 
newly developed quality features in a new physical layout. The new 
arrangement is designed to combine optimum functional advantage 
and operating convenience with improved accessibility, adjustability, 
and interchangeability of all components as far as possible on an inte- 
gral subassembly basis. There is also improved functional inte- 
gration between the optical system and film mechanism, which to- 
gether constitute the PR-31 recorder. 


Grateful acknowledgment is tendered the many individuals, both 
within and without the RCA organization, whose thoughts, sugges- 
tions, and efforts contributed to the design and construction of this 



optical system. Specific acknowledgment is made of the contribution 
of Messrs. W. V. Wolfe, A. C. Blaney, O. B. Gunby, M. E. Collins, 
E. W. Kellogg, G. L. Dimmick, C. E. Kittle, and the late J. L. 


(1) B. Kreuzer, "Noise reduction with variable-area recording," J. Soc. 
Mot. Pict. Eng., vol. 16, p. 671; June, 1931. 

(2) G. L. Dimmick, "The RCA recording system and its adaptation to 
various types of sound-track," /. Soc. Mot. Pict. Eng., vol. 29, p. 258; September, 

(3) H. J. Hasbrouck, J. O. Baker, and C. N. Batsel, "Improved noise re- 
duction system for high-fidelity recording," /. Soc. Mot. Pict. Eng., vol. 29, p. 
310; September, 1937. 

(4) E. W. Kellogg, "The ABC of photographic sound recording," /. Soc. 
Mot. Pict. Eng., vol. 44, p. 151; March, 1945. 

(5) M. E. Collins, "A de luxe film recording machine," J. Soc+Mot. Pict. 
Eng., vol. 48, p. 148; February, 1947. 

(6) U. S. Patent 2,158,307. 

(7) G. L. Dimmick, "A newly developed Jight modulator for sound re- 
cording," /. Soc. Mot. Pict. Eng., vol. 49, pp. 48-57; July, 1947. 

(8) G. L. Dimmick, and A. C. Blaney, "A direct-positive system of sound 
recording," J. Soc. Mot. Pict. Eng., vol. 33, p. 479; November, 1939. 

(9) G. L. Dimmick, "A new dichroic reflector and its application to photocell 
monitoring systems," /. Soc. Mot. Pict. Eng., vol. 38, p. 36; January, 1942. 

(10) G. L. Dimmick, "The RCA recording system and its adaptation to 
various types of sound track," /. Soc. Mot. Pict. Eng., vol. 29, p. 258; September, 

(11) G. L. Dimmick and H. Belar, "An improved system for noiseless re- 
cording," /. Soc. Mot. Pict. Eng., vol. 23, p. 48; July, 1934. 

(12) D. J. Bloomberg and C. L. Lootens, "Class B push-pull recording for 
original negatives," /. Soc. Mot. Pict. Eng., vol. 33, p. 664; December, 1939. 

(13) American Standard Z22.40-1946, /. Soc. Mot. Pict. Eng., vol. 46, p. 292; 
April, 1946. 

(14) G. L. Dimmick and H. Belar, "Extension of the frequency range of film 
recording and reproduction," /. Soc. Mot. Pict. Eng., vol. 19, p. 401; November, 

(15) R. O. Drew and S. W. Johnson, "Preliminary sound recording tests with 
variable-area dye tracks," /. Soc. Mot. Pict. Eng., vol. 46, p. 387; May, 1946. 

Cathode- Ray -Oscillograph Images of 
Noise- Reduction Envelopes* 



Summary A method of using a standard cathode -ray oscillograph to pre- 
sent low- frequency or direct -current conditions is described. In the 
interest of sound on -film recording the paper describes how an electronic 
switch is used to generate repetitive pulses of audio signals as a second 
electronic switch is used to pick up the signals and the resulting noise- 
reduction-bias envelope and place them in reference positions on the 

THE MOST ACCURATE method of measuring noise-reduction "enve- 
lopes" or direct-current pulses is (probably) the high-speed re- 
cording oscillograph. This instrument involves a delay before the 
graph may be developed and read and it lacks reference marks unless 
a dual unit is used. Graphs can be compared before and after ad- 
justments but the changing results of an adjustment cannot be 
shown without considerable comparison and delay. 

The use of two electronic switches of standard design, a cathode- 
ray oscillograph, a sine-wave audio oscillator, and an optional high- 
pass filter make possible the generation of ideal reference signals 
and presentation of both the reference signal and envelope on the 

Fig. 1 shows a block schematic of the Western Electric Type RA- 
1124 Noise-Reduction Unit which was the "guinea pig" for this work. 
In typical operation the speech amplifier is bridged across the record- 
ing circuit. The signal is amplified, diode-rectified, and "shaped" by 
the low-pass filter of proper timing characteristic. The timing varies 
with use. Low-speed filters are used with single sound tracks and 
high-speed filters are normally used with push-"pull sound tracks. 
The voltage output of the filter is used to modulate a 20-kilocycle os- 
cillator output. The modulated 20-kilocycle is then amplified, recti- 
fied, and ripple-filtered to provide bias current for the light modula- 
tor. During silent intervals the bias current closes the modulator to 
a predetermined value. As speech is applied to the light modulator 
the bias is removed according to the "shape" of the timing filter. 
* Presented April 21, 1947, at the SMPE Convention in Chicago. 





The clearance between the biased spacing of the modulator and signal 
peak is referred to as margin. If the bias spacing fails to provide 
sufficient clearance for the signal, particularly at the beginning of a 
speech signal, distortion or "clipping" of the signal peaks occurs. 

A light-valve variable-density system was used with this work al- 
though a similar analysis may be made with any variable-area system. 

In Fig. 2, when the signal is graphically applied to the lower ribbon 
of the light valve and the noise-reduction envelope to the upper rib- 
bon, the functions of signal and noise reduction may be separated 
and more easily illustrated. The variable-area equivalent is the 
familiar unilateral sound track. 










20- KG 







Fig. 1 Block schematic of RA-1124 noise-reduction unit. 

The method used to place the signal and noise-reduction envelopes 
in their proper graphical relationship on the oscillograph screen makes 
use of this type of illustration. 

Fig. 3 shows the test signal. The signal is a pulse of 700-cycle sine 
waves followed by a blank interval, another pulse, another blank in- 
terval, and so on. The pulse amplitude and rate are varied over de- 
sired limits. Each pulse, depending on length, amplitude, and repe- 
tition rate will, when connected to a properly adjusted noise-reduction 
system, generate a noise-reduction envelope whose "shape" will have 
a definite relationship to the pulse characteristic, as shown in Fig. 4. 




Adjusted vertically and timed horizontally on the cathode-ray oscillo- 
graph the attack and decay times are shown graphically and may be 
read directly in milliseconds. The effect of margin on "clipping" is 
seen; that of "threshold" adjustment on margin may be determined. 
The test circuit requires explanation. Fig. 5 shows a functional 
schematic and a typical pattern observed on the oscillograph. In 
practice a 700-cycle sine- wave signal is connected to both input A and 
input B of electronic switch No. 1 . Practically, the switch is a double- 
throw switch switching from the output of attenuator A to the out- 
put of attenuator B at any adjustable square- wave frequency between 


Fig. 2 Graph of test signal and noise-reduction envelope. 

Fig. 3 Pulses of signal only. 

2 and 3000 cycles per second. To illustrate: with the switching rate 
adjusted to 4 cycles per second, a signal on the output of attenuator 
A would be passed through the switch for one eighth of a second or 
125 milliseconds. Then the switch changes to the output of attenu- 
ator B. The switch is disconnected from either attenuator for ap- 
proximately one fortieth of a millisecond. The signal, if any, on the 
output of attenuator B is now passed through the switch for one 
eighth of a second or 125 milliseconds. The switch then transfers 
back to A in one fortieth of a millisecond and the signal A is passed 
for its interval, and so on. 

With the attenuators adjusted to identical output levels an essen- 
tially steady signal appears on the output of switch No. 1 with a small 
transient every 125 milliseconds. This condition is used for line-up, 
bias, and margin adjustment. 




After line-up the signal through B is completely attenuated and 
there appears from A, through the switch, the pulse of predeter- 
mined rate and amplitude. The oscillograph horizontal-sweep circuit 
is adjusted to synchronize with the pulse rate or submultiple of switch 
No. 1. Many amplifiers generate a low-frequency transient of varying 
amplitude when passing pulses or "blocks" of tone. To remove these 
from the pattern, a high-pass filter is used immediately before the 
light valve and noise-reduction circuit. 

Examination will show the connections to the electronic switch No. 
2. Input C is connected to the modulating signal and input D is con- 
nected to the noise-reduction leads, or light valve. For the test, the 
signal is not connected to the light-valve circuit. Only the noise- 
reduction envelope is applied to the valve. . The oscillograph vertical 


Fig. 4 Pulses of signal and noise-reduction envelope. 

plates input is connected to the output of switch No. 2 which is ad- 
justed to a 500-cycle switching rate. During the 1 -millisecond inter- 
val when switch No. 2 is connected to C the signal on the output of at- 
tenuator C is passed through the switch and is seen on the oscillo- 
graph. Similarly, during the 1-millisecond interval when switch No. 2 
is connected to D, the signal on the output of attenuator D is passed 
through the switch and is seen on the oscillograph. Normally, a use- 
less jumble would be seen because the electrical axis of signal C is 
congruent with that of signal D and it is difficult to segregate the in- 
termixed patterns. To make separation possible, a biasing supply is 
designed into the switch. Effectively it appears as a pair of variable 
voltages of opposite polarity placed in series with the output of each 
attenuator. These potentials, superimposed on the signals of each at- 
tenuator output, separate the signal from the noise-reduction envelope 
and the pattern shown is obtained. A low-frequency signal is shown 
for ease in illustration. By adjustment of these potentials and the 
attenuators C and D, the pattern on the oscillograph may be adjusted 
to illustrate any line-up condition of level and margin. Then the at- 
tenuator A may be adjusted to indicate the results of various signal 
levels, while the pulse rate of electronic switch No. 1 may be adjusted 




to any multiple of the oscillograph sweep rate to show the effects of 
pulse rate. 

The use of a 500-cycle switching rate on electronic switch No. 2 per- 
mits a short line of the envelope or signal pattern to appear every 2 
milliseconds and for 1 millisecond's duration alternately on the 
upper (noise-reduction) and lower (signal) pattern. Faint vertical 
lines of one fortieth of a millisecond duration appear 1 millisecond 
apart. It is then possible to determine quickly and accurately the 
time constants. 



NO. I 







PLATES ^-., 








Fig. 5 Block schematic of electronic switches and record- 
ing system plus typical detailed pattern. 

In Fig. 6, the upper patterns show a 700-cycle envelope of 125 milli- 
seconds' duration and the resulting noise-reduction envelope. The 
700-cycle signal is used to provide a signal near the center of the au- 
dio-frequency band whose interference with the 500-cycle switching 
rate would be random enough to show a "block" of signal rather than 
a distracting pattern. 

The signal level, 6 decibels below unbiased overload, refers to a 
signal whose amplitude is 6 decibels below unbiased light-valve over- 
load, or clash, of a light valve whose ribbons were normally spaced 
1 one thousandth of an inch apart. 

To set up this pattern a 4-cycle switching rate is used with the 700- 




cycle signal. After margin adjustment with a steady signal the sig- 
nal through attenuator B is eliminated. The signal measures 1 one 
thousandth of an inch peak to peak and on the lower ribbon would 
cause the ribbon to move one-half thousandth of an inch above and 
below its rest position. The noise-reduction ribbon at rest is spaced 
exactly 1 one thousandth of an inch from the signal ribbon at rest. 
Biased to 10-decibel noise reduction, this ribbon would position itself 
approximately 3 ten thousandths of an inch from the signal ribbon. 
When the signal is applied to the noise-reduction-bias cancellation 









Fig. 6 Detail of 125-millisecond pulse and noise-reduction 
envelope. Also 50-millisecond patterns. 

amplifier and rectifier the noise-reduction ribbon would, with a 6-deci- 
bel margin and a typical high-speed filter, move to 1 one thousandth 
of an inch from the signal ribbon in approximately 10 milliseconds. 
After the signal was removed from the noise-reduction unit, the rib- 
bon would move again to the 3 ten thousandths of an inch spacing in 
approximately 30 milliseconds. In these filters of essentially constant 
"slope" the attack and decay-time ratings are those of 90 per cent 
voltage change. High- and low- speed filters usually differ only in at- 
tack interval. Observe the difference in the amount of "clipping" 
and accompanying distortion. 

At the time these patterns were being traced the techniques of 
photographing cathode-ray-oscillograph images were not available to 
the author. However, the patterns have been traced from the oscillo- 
graph screen, and redrawn without French curves. 




The lower patterns show the pulse rate increased to 10 cycles and 
each pulse shortened to 50 milliseconds' duration. The noise-reduc- 
tion-to-signal ratio is the same as that for the 4-cycle rate because 
there is ample time for a complete noise-reduction cancellation and 
return cycle. 

In Fig. 7, the upper 15-cycle patterns show the decay and attack 
curves beginning to overlap. The lower 20-cycle patterns show that, 
after the first pulse, clipping is not possible with either high- or low- 
speed filters. In Fig. 8, the upper patterns show how with short 







Fig. 7 33- and 25-millisecond patterns. 

pulses, it may require a considerable time for the 6-decibel margin 
to be reached with the low-speed filter. If the pulses are very short, 
as in the lower figure, the 6-decibel margin may not be reached. 

In generating the pulses used in these tests, the electronic switch 
No. 1 splits many cycles. The upper pattern of Fig. 9 is typical. 

Observe the incomplete cycles at the start and termination of the 
pulse. These incomplete cycles contain many higher frequency 
transients and pulse-rate harmonics. 

A 12-decibel equalizer is inserted in the line after the switch. The 
equalizer has a 10-decibel rise between 700 and 9000 cycles. The 
700-cycle margin adjustment is remade and the lower pattern of 
Fig. 9 is obtained. The peak amplitudes of the equalized harmonics 
range up to 10 decibels above the 700-cycle normal. 

In all subsequent patterns the pulse rate is 4 cycles and the pulse 











Fig. 8 15- and 10-millisecond patterns. 

length 125 milliseconds. The signal and the noise-reduction enve- 
lopes are altered in vertical scale for ease in illustration. 

Fig. 10 illustrates the effect of transient peaks in the signal or the 
noise-reduction envelope. The upper patterns are for the normal 
pulse. The lower patterns contain transients at the beginning and 
end of each pulse and are somewhat similar to many sounds encoun- 
tered in speech and music. Contrary to some opinions, the peaks in 
the "front" of a modulation envelope do not cause the attack slope to 
become greatly exaggerated as most of the energy is used in charging 
the input capacitors of the filter ; and the amplifier-rectifier stage pre- 
ceding the filter does have some impedance. They do increase the 
slope slightly and may cause a slight overcancellation. A peak rising 



Fig. 9 Pattern with incomplete cycles equalized. 




from a steady-state signal will cause a greater proportional disturb- 
ance than one at the beginning of a wave train. 

In Fig. 11 and following graphs these effects are illustrated. Until 
the signal envelope is below threshold adjustment levels, the first 
peak is of lower amplitude than the peak at the end of each wave 
train. Threshold control requires a brief explanation. Normally 
any signal applied to the noise-reduction unit would start the cancella- 
tion process. By adjusting a fixed-delay bias on the grid of the modu- 
lator tube weak signals, whose amplitudes require no wider light- 
valve spacing, will not cause bias cancellation. Thus the average 









Fig. 10 Pattern showing envelope affected by transients. 

spacing of the light valve remains less than it would be if no threshold 
were used. Consequently, less "breathing" of background noise is 
heard on reproduction of the film. The patterns are similar, except 
for attack slope, for both high- and low-speed filters. 

In Fig. 11 a signal of 14 decibels below unbiased overload was used 
at a 4-cycle rate and 125-millisecond length. The margin was ad- 
justed to 6 decibels at 6 decibels below unbiased overload. The 
threshold of cancellation action was varied from 25 to 16 decibels 
below unbiased overload. Note how threshold adjustment reduces 
noise-reduction envelope movement with low signal levels. 

In the lower pattern the equalized pulse is used. Note that the 
first (attack) peak is of lower peak amplitude than the second peak. 




As the threshold approaches the signal level, the cancellation is re- 
duced and the first peak becomes simi'ar to the second peak. 

In Fig. 12 the flat pulse of 18 decibels below unbiased overload is 
used. Observe how with a 16 threshold adjustment no cancellation 
takes place. In the lower pattern the equalized pulse is used. As 
the threshold nears the signal level the peaks become symmetrical. 
In Fig. 13 the equalized pulse of 25 decibels below overload is used. 
The peaks cause no disturbance with the 16 threshold adjustment. 
In judging these results the use of threshold control and the disuse 







Fig. 11 Pattern, signal at 14 decibels below un- 
biased overload, showing effects of threshold. 

of pre-equalization is indicated. However, this must be weighed 
against inherent noise reduction of pre- and postequalization and 
cancellation of noise-reduction disturbance in push-pull original re- 
cordings. The results indicate that clipping of staccato signals and 
sharp wave fronts may be greater than expected because the first peak 
does not contribute as much toward cancellation as might be desired. 
The possibility of transients on the bias leads has been advanced. 
With some filter units, oscillograph patterns show a transient at the 
end of the decay interval. This varies with the type of filter, signal 
level into the margin amplifier, threshold adjustment, and so on. 










Fig. 12 Pattern, 18 decibels below unbiased 
overload, showing effects of threshold. 

In Fig. 14, upper left, is a typical pattern obtained with the switch 
No. 2 input D across the speech rectifier output and with the timing 
filter removed. A typical unfiltered full-wave rectified pattern is 
seen. The upper right pattern is obtained with the input D across 
the speech-rectifier output with the filter in place. The slight attack 
slope is due to the time necessary to charge the input capacitor. The 
shape of the transient at the end of the decay slope varies with level, 
threshold adjustment, and individual filter unit over the limits shown. 

The lower left pattern is obtained with the input D across the filter 
output. Greater slope is apparent on both the attack and decay. 
The transient changes in shape and seems delayed about 20 millisec- 
onds. As previously explained, with this type of noise-reduction unit 
the output of the filter controls a modulator tube which in turn 


- 16 




Fig. 13 Pattern, signal at 25 decibels below 
unbiased overload, showing effects of threshold. 




modulates a 20-kilocycle signal which is later amplified, rectified, fil- 
tered, and applied to the light-valve circuit as bias. The lower right 
pattern is obtained with the input D across the bias leads. The slopes 
and transients are altered by the characteristic of the modulator tube. 
Examination of all the components of the R A- 11 24 noise-reduction 
unit discloses no particular trouble or remedy. The transient is due 
to the controlled damping of the timing filter. It varies with indi- 
vidual filters and is most evident with the low-speed-type filter. It 
could be reduced by the retuning of the filter but this is usually in- 
volved. The amplitude of the transient is such that it, for about 30 







Fig. 14 Patterns showing transients in timing filter. 

milliseconds, alters the noise reduction about 1 decibel. Practically, 
this can be ignored. 

A poor tube in the margin amplifier caused the effects shown in Fig. 
15. Overloading on positive peaks caused the bias and the plate 
voltage to change and the patterns shown resulted. The transient 
at the end of the envelope is caused by the low-frequency wave gen- 
erated as the bias and plate voltage shifted back to normal after the 
signal was removed. 

The oscillograph used may be of any average type. The tube may 
be of the PI phosphor medium-persistence type although the P7 or 
P2 long-persistence types would be desirable. Only one feature 




should be stressed, that of a linear horizontal sweep at frequencies as 
low as 4 cycles per second. Because the oscillograph vertical ampli- 
fier receives its information at 500 cycles, and above, the usual dif- 
ficulties of low-frequency or direct-current presentation are avoided. 

This adaptation of electronic switches to the visual inspection of 
noise-reduction envelopes is one of the many utilizations of such equip- 
ment. Low-frequency and direct voltages may be read with high- 
frequency switching rates. The switch may be used to transfer the 







Fig. 15 Patterns showing transients generated 
in margin amplifier. 

oscillograph back and forth between the input and output of an am- 
plifier, and after the patterns are adjusted to equal amplitude, by 
comparison check amplitude distortion, frequency characteristic, 
and phase distortion quickly. The switch used to time pulses or 
"blocks" of signal may be used to check time constants and "thumps" 
of compressors and expanders. A typical use is to send pulses of 
700-cycle signal into a limiter amplifier and audibly adjust the bal- 
ancing controls for minimum "thumps". 

The switches of the author are homebuilt but are similar to de- 
vices available on the instrument market.* 
* Allan B. DuMont Laboratories, Inc. 

A Motion Picture 
Film-Developing Machine* 



Summary This paper describes a motion picture film developing ma- 
chine which operates on a principle which has been used for a long time. It 
has been designed with the intention of providing convenience and flexibility 
of operating setup for various processes. Thyratron controls are used to 
provide uniform tension at the head and takeup, and to control speed of the 
main drive. Air agitation is provided. 

THIS MACHINE is designed to fit the needs of both small and me- 
dium-sized motion picture laboratories. It is made in models for 
both 35-mm and 16-mm film, and to handle all processes in general 
use, at speeds of from thirty to one hundred feet per minute. It is 
of small size in relation to its capacity. 

The basic principle of operation of this developing machine has 
been in use for may years and is not new. The general design of the 
machine will be described rather than a specific model. Fig. 1 is a 
photograph of one of the machines installed with the drying cabinet 
in the same room with the wet section; Fig. 2 is a schematic drawing. 

The head assembly is made with two spindles, each holding a 2000- 
foot roll, either on reel or core. Film can feed into the machine from 
either spindle. In use, the two spindles permit one to be always 
ready, loaded with a new roll of film, to facilitate rapid splicing onto 
the preceding roll end. The film feeds from a roll into the elevator, 
which is kept at full-load position by means of a thyratron-controlled 
brake on the spindles. 

Another electrically operated brake is located on a sprocket roller 
at the entrance to the elevator. When a feed roll is exhausted, this 
brake automatically stops feed into the elevator, leaving a loose end 
of slack film ahead of the elevator to be spliced onto the new roll. 
The pressing of a brake release button after a new roll is spliced on, 
causes the elevator to refill. An audible warning signal is provided 
on the head, which operates whenever a roll runs out or when the 
elevator starts to rise. 

The drive is run by a thyratron-controlled motor. It operates by 
means of an endless chain, which engages a chain sprocket attached 
* Presented April 22, 1947, at the SMPE Convention in Chicago. 




to the top roller shaft on each developing rack. Processing racks are 
held in place only by gravity, and may be removed individually, 
without tools. Wet end racks are interchangeable. They can be 
engaged with the drive at intervals of three inches along the length 
of the wet end of the machine. 

The bottom-rack rollers are mounted on a free-floating shaft, which 
may be raised or lowered to decrease or increase the amount of film 
on a rack. The amount of film on a rack is indicated by a flag rod 

Fig. 1 Typical developing machine installation. 

which raises or lowers corresponding to the amount of film on the 
rack. Tanks are all individually removable and are interchangeable. 
Any combination of tanks may be set up within limits of the machine 
frame size, to handle any desired process. 

Air agitation is provided in all tanks, by means of a system similar 
to that described by Ives and Kunz. 1 The film passes through a 
cascade wash system, and thence through a pneumatic squeegee into 
the dry box. Drying is by high-velocity filtered air, with provision 
for dehydration and/or heating, if required. A cascade system is 
employed in drying. The dry box uses racks similar in design to 




the wet-end racks. They are driven by a continuation of the same 
endless-chain drive which operates the wet end. Transparent plastic 
is used for the dry-box top, which may be opened to expose the 
drive and racks completely. All dry-box racks may be removed 
easily without tools, as they are held in place only by gravity. This 
facilitates the periodical cleaning of the dry box, and permits flexi- 
bility in drying tune as racks may be cut in or out as desired. 

The film passes from the final drying rack onto an elevator, en- 
closed in the dry box, which starts into operation when a reel is 

Fig. 2 Schematic diagram of developing machine. 

removed from the take-off. This elevator holds sufficient film to 
allow the machine to operate while a new reel is being started. 

On leaving the dry box, the film passes over a roller which can 
rotate in one direction only, preventing back-up of film into the dry 
box while the take-up reel is being changed. 


The film path through the machine is over a series of racks similar 
to the one shown in Fig. 1. The top shaft is mechanically driven 
with a single sprocket roller on it next to the end where the film 
enters the rack. The other top rollers are free on the shaft. The 
bottom rollers are all free to rotate on a fixed shaft held by a carriage 
that can slide vertically in the rack frame. 


Neglecting friction, the tension of the film is therefore equal to the 
weight of the bottom carriage divided by the number of strands of 
film supporting the carriage. However, friction of the rollers and of 
the film passing through the solutions upsets the equal distribution of 
the tension. This effect is minimized in the following way : 

The retarding force produced by the bottom rollers is approximately 
compensated for by a driving force produced by the top rollers. 
The latter (the driving force) arises because the pitch diameter of the 
sprocket roller is smaller than that of the free rollers, and hence the 
shaft rotates faster than the rollers. 

The frictional torque of a roller on a shaft depends upon the 
bearing surfaces, the diameter of the shaft, the load, the type of 
lubrication, and in most cases upon the relative angular velocity of the 
roller with respect to the shaft. 

In order to balance the driving friction and the retarding friction, 
some of the above factors can be varied. The bottom-rack rollers 
have a smaller shaft than the top rollers, but the relative speed of the 
roller with respect to the shaft is less for the top rollers. 

If the balance were perfect the sprockets would neither drive nor 
hold back the film. That the balance actually achieved is quite 
good, can be shown by a stroboscope or by running a length of 
unperf orated film through the machine. 

The bottom rollers have stationary washers between rollers to 
prevent them from locking together as a unit with static friction. 
This facilitates compensation for shrinkage or expansion, because 
each roller may rotate with a slightly different velocity. 

The head elevator is similar in principle to the racks, except that 
none of the roller shafts is driven. 

The friction brake on each feed-in roll spindle is actuated by an 
electromagnet controlled by a thyratfon tube in such a way that the 
braking force on the feed-in spindle depends only upon the vertical 
position of the bottom rollers of the elevator. Since the weight on 
the bottom rollers remains constant at all times, the tension on the 
film remains constant and does not depend upon the diameter of the 
feed-in roll. The take-off operates in a similar way as it also is 
controlled by means of a thyratron and electromagnet to maintain 
uniform tension regardless of the change in size of the take-off roll. 


(1) C. E. Ives and C. J. Kunz, "Solution agitation by means of compressed 
air," /. Soc. Mot. Pict. Eng., vol. 34, p. 364; April, 1940. 

Television Remote Operations* 



Summary Remote operation implies the pickup of program matter out- 
side the studio and station. Equipment and personnel in the field, in the 
station, and interconnecting are always involved in a "remote". Field opera- 
tions usually require two cameras, preferably employing image-orthicon 
tubes. Studio or film images and sound can be dubbed in between field 
sequences, a procedure useful for commercial announcements. A relay 
receiver, a picture switching or mixing device, monitors, oscillograph, and 
audio-control equipment are required at the station for such operation. 
These combined facilities provide unsurpassed program possibilities. 

REMOTE OPERATION is the term used by television broadcasters for 
the procedure of picking up program matter from points outside 
of their studios, transmitting, or relaying the image signals and sound 
into the station, and broadcasting them. It usually applies to intra- 
city operation as distinguished from intercity or interstation relaying. 
The relay transmitting facilities are usually portable in this type of 
operation, while the receiver location is fixed. 

By use of suitable remote facilities a station can broadcast a great 
variety of public-interest subjects at the instant of occurrence. In 
this way it fulfills a desire of the average individual that cannot be 
fulfilled by any other medium. Hence this type of broadcast has 
strong appeal and is extremely popular. The subject matter is 
usually of a nature that has been developed for visual as well as 
auditory appeal, the best example being sports, which can be broad- 
cast without costly special staging for television. In view of these 
factors remote operations may well become the backbone of television 
programming and are, therefore, worthy of thorough development. 

Another point not to be overlooked in the development of remote- 
operation techniques is their possible future application to theater 
reproduction. Any remote operation involves three main divisions: 
the field, the interconnecting facilities, and the station. 


Typical field operations require at least two cameras. Types 
employing the well-known image-orthicon tube are best adapted to 
the tasks, chiefly because of their remarkable light sensitivity. The 
* Presented April 22, 1947, at the SMPE Convention in Chicago. 



broadcaster seldom has control over illumination of his subjects out- 
side of his own premises, especially when working out of doors, where 
the incident illumination varies by a factor of 1 to 1000 from a cloudy 
winter day to summer sunshine. The level may sink to 2 or 3 foot- 
candles or less before a game is called on account of darkness. Indoor 
events such as boxing, water polo, and many others are frequently 
illuminated in a hit-or-miss manner that varies from as low as 15 
foot-candles up to 500. These wide variations can be taken care of 
in image-orthicon equipment by lens diaphragms variable from //1. 9 
to//22. Filters are sometimes added on sunny days out of doors, giv- 
ing an added benefit in improved color response. 

While image signals can be obtained with incident light as low as 
one foot-candle, the average image-orthicon tube requires about 50 
to produce a signal sufficiently free of shot and thermal noise to be 
satisfactory for relaying and broadcasting. Noise is added in the 
relaying process and, while small in a good link, it cannot be neg- 
lected. Hence it is wise to have conditions as favorable as circum- 
stances will permit at the source. Where light levels of less than 50 
foot-candles are encountered indoors, and it is possible to supplement 
existing illuminants for the television pickup, it is desirable to do so. 
Artistic lighting is uncalled for in sports and many other events and 
simple overhead illumination is adequate. Lenses ranging in focal 
lengths from 2 to 24 inches are used on the cameras providing hori- 
zontal angles of view of 30 to about 2 degrees. This gives a great deal 
of latitude in placing cameras. For football they can be placed in 
press booths or even above the press booths. For boxing or wrestling 
the cameras can be placed anywhere from 20 feet away from the ring 
to 150 feet. Other events can be handled in proportion to their 
scope. Fig. 1 shows a typical setup. 

Any television cameras, including the image-orthicon type, must 
have control equipment associated with them. This control equip- 
ment includes the synchronizing impulse and scanning source, usually 
referred to as the synchronizing generator. It also includes video 
and scanning amplifiers, monitors, oscilloscopes, and numerous 
controls on the camera action. All of these facilities are packaged in 
suitcase-sized units for convenient handling. However, some of 
them weigh 65 pounds or more. When combined with audio equip- 
ment, cables, spare-parts kits, and tool boxes, they add up to a dozen 
packages. It has been the practice of some operators to carry this 
equipment to a vantage point within a building, stadium, or arena. 




In some instances this is necessary, but in the majority of cases it is 
not. Very satisfactory operation has been achieved in most cases 
at WBKB by maintaining this gear in the light truck by which it is 
taken to the site. The equipment is located in a semifixed state on 
an operating bench as may be seen in Fig. 2. Up to 350 feet of 
cable are used on each of two cameras to reach advantageous loca- 
tions. In this way, only the camera cables, microphone wires, and 
cameras have to be carried into buildings; up and down ramps, 

Fig. 1 Typical remote camera setup. 

elevators, and stairs. This saves labor in setting up and avoids 
having extra help attached to a remote crew who would not have 
duties during operation. 

The minimum crew for an operation in a location where preliminary 
work has been done consists of two cameramen, one field director, 
two operating technicians, and an electrician, in addition to an an- 
nouncer and a spotter, if required. The field director and technicians 
usually operate in the truck. Under favorable circumstances they 
can set up and commence operations in less than one hour. 


During operation one technician operates the controls on the 
camera apparatus; the other "rides gain" on the sound and looks 
after the relay transmitter. The electrician assists with setup and 
serves as relief operator and emergency repairman. The field direc- 
tor co-ordinates the cameramen's work, switches pictures, and acts 
as liaison with the main station director in case of switches back to 
the studio for commercial announcements. 

Fig. 2 Technical operator's position in remote truck. 

In cases of frequent broadcasts from the same location, such as 
baseball games during the season, it is worth while to locate equip- 
ment semipermanently in a broadcast booth convenient to camera 
locations and the announcer's position. 

It is helpful, particularly in sports, to provide the announcer with a 
picture monitor. This should be connected to the output of the 
control equipment and can be fed by a small coaxial cable up to 1000 
feet in length, perhaps more if needed. An ordinary table-model 
home receiver equipped with carrying handles and a cable connection 
into its video amplifier is convenient for this. 

58 BROLLY January 

A useful piece of additional equipment maintained on tap for 
remote operations is a gas-engine generator. The complete two- 
camera television chain with relay transmitter and audio equipment 
requires a little over five kilowatts. A 10-kilowatt 60-cycle-per- 
second, 115-volt, single-phase alternator driven by a four-cylinder 
gas engine is mounted in a two- wheel trailer which can be towed 
behind the equipment truck to any location where public-utility 
services are not available. Its excess capacity over and above ap- 
paratus requirements is sometimes used for lights. Relays have been 
made from the apparatus truck while in motion by using this source 
of power. 

Audio equipment in the field consists of a Western Electric Type 
22D portable speech-input equipment with from one to three micro- 
phones. Dynamic microphones are used in may instances because of 
their sturdiness and insensitivity to wind or drafts. This is an 
important consideration out of doors. Low-impedance microphone 
circuits are favored for their freedom from pickup of electrical dis- 
turbances in cables which are frequently 200 or 300 feet long. 

Considering the foregoing it will be apparent that rather extensive 
intercommunicating facilites are required in the field and between 
there and the parent station. Basically these consist of two circuits, 
a technical-order circuit and a program-cuing circuit. The first 
interconnects the cameramen with the technical operator and ties 
him in with the relay operator and the parent-station technical 
personnel. The other circuit interconnects the announcer and 
cameramen with the field director and through him with the parent- 
station program director. The field director can also monitor the 
program sound. 


Two basic functions and two auxiliary functions are required of 
the interconnecting communications between the field and the parent 
station. To dispose of the simpler ones first, the technical-order 
circuit and the program-cue circuit are most conveniently connected 
back to the station by ordinary telephone lines run to a site con- 
venient to the location of control equipment. When operation is 
from the truck the lines are terminated in a building at any point 
nearest to where it is to be parked. They are extended by temporary 
flexible leads to the truck when operating. For program sound the 
output of the speech amplifier is fed to a telephone program cricuit 


which is also terminated in a convenient spot with the order wires. 
The program sound is fed to this line at zero level, and it is usually 
equalized at the station end only. Telephone lines for these three 
functions are rented by the month for locations where remote broad- 
casts are done weekly or oftener. 

The remaining interconnecting or relay function, perhaps the most 
important and the one posing the most problems, is that of getting 
the picture signal to the parent station. This must be accomplished 
for a frequency range of 60 cycles per second to 4 megacycles or more 
with good response to transient-wave shapes composed of frequencies 
in this range and with the least possible injection of noise or extra- 
neous interfering signals. 

The intracity relaying of video signals can be accomplished by 
telephone lines, coaxial cable, and very-high-frequency radio. Tele- 
phone lines of the ordinary type must be highly equalized at intervals 
of only one to one and one-half miles. 1 Apparatus for this service as 
\vell as coaxial lines or other special conductors have not been readily 
available in Chicago up to the date of this paper and the cost of such 
service is quoted at a high figure. Experience at Station WBKB, 
upon which this paper is based, has been confined to radio relaying. 
Line transmission undoubtedly has merits in freedom from noise and 
interference but for mobility and economy of operation, very-high- 
frequency radio-beam equipment cannot be surpassed. Even in the 
matter of first cost, based on present quotations, the radio-relay 
equipment offers a decided economy. Modern microwave apparatus 
employing frequency modulation can offer a bandwidth scarcely 
equaled by line equipment available and, for distances of a few miles, 
can probably equal line facilities in the matter of noise or interference. 2 

Station WBKB so far has not been able to enjoy the advantages of 
this up-to-the-minute type of equipment, yet it has established an 
enviable record of achievement in remote operations with less-elabo- 
rate equipment which is worthy of special mention. 

Radio relaying in a large city like Chicago is somewhat akin to a 
short person viewing a motion picture in a crowded theater. Every- 
where he sits someone's head is in the way. Very-high-frequency 
waves do not penetrate through buildings very well and the higher 
the frequency the more severe this limitation becomes. In Chicago 
the highest points for receiving relayed signals giving unobstructed 
paths from the greatest number of points do not happen to be at or 
even adjacent to the location of the station, so relay operation 

60 BROLLY January 

by WBKB has been done best in two steps, requiring two sets of 
equipment. An important part of this equipment is installed as a 
repeater station atop one of the tallest buildings in the Chicago loop. 
The relationship of the remote operation to the parent-station facili- 
ties and the function of the repeater station are illustrated in Fig. 3. 

The basic unit of relay equipment at WBKB is a 210-megacycle 
transmitter of 20 watts output, amplitude-modulated. Double- 
sideband transmission is used with a frequency response out to 4 J /2 
megacycles. This unit is carried with the mobile camera equipment 
and at most locations is operated in the truck. Its output is fed to 
antenna arrays of varying numbers of elements depending upon the 
distance over which the relay is to work. These antenna arrays are 
usually set up in advance of a broadcast and if repeated broadcasts 
are to be made from any location, one of them is left there. On a 
succeeding broadcast it is only necessary to drive the truck to the 
location and connect the antenna lead. Arrays of 20 half-wave 
dipcles having gains of about 14 decibels are used in most locations. 
With this transmitting and antenna equipment satisfactory relays have 
been conducted from points up to 15 miles distant from the station. 

Reception on top of a tall building in the Chicago Loop is accom- 
plished with an eight-element antenna, four of the elements being 
parasitic reflectors. The receiver is a superheterodyne with one 
radio-frequency stage, five intermediate-frequency stages, and one 
cathode output video stage. The output of this receiver is monitored 
with an oscilloscope and a television receiver before being coupled 
into the succeeding relay equipment. This is a 1300-megacycle, 
amplitude-modulated apparatus of about one watt output. Its an- 
tenna is a dipole with parabolic reflector. The beam is directed from 
the building, as shown in Fig. 4, to the building where the studios 
and transmitter are located. The distance is only about one-half 
mile. The circuit is very reliable, unaffected by weather conditions, 
and contributes a negligible amount of noise to the system. 

Reception of this 1300-megacycle beam is accomplished with a 
half-wave dipole antenna and 60-degree corner reflector. The 
receiver employs a cavity-tuned oscillator, crystal mixer, and three 
stages of intermediate frequency. It has been found that the noise 
level at the output of the receiver, for a given signal input, depends 
very much upon the forward-to-inverse conductivity ratio of the 
crystal mixer. This ratio ranges from 3 to 1 up to 100 to 1 in various 
crystals as measured with low direct voltage. A high forward 




62 BROLLY January 

conductivity and low inverse conductivity provides the highest signal- 
to-noise ratio. The output of the second detector of this receiver is 
a cathode output video stage feeding a 73-ohm coaxial line extending 
to the control room. 


Entering the station control room from a remote location are the 
three telephone lines and the one coaxial line from the relay receiver. 
The technical-order wire has taps leading to the repeater station and 
the relay receiver at the station building. It terminates on the desk 
of a technical operator in the control room. From there he is in touch 

Fig. 4 1300-megacycle relay transmitting equipment at 
repeater station. 

with other station personnel. Fig. 5 shows the master-control 
room at the station through which all the relay and communication 
circuits pass and are co-ordinated with station operations. The 
program-cue line terminates at the director's console in the control 
room. The director is in communication with other program per- 
sonnel at the station and with the technical operator. The program 
line passes through an equalizer, an amplifier that makes up a loss 
of some 50 decibels in the lines and equalizer, and thence into a nemo 
circuit on the audio console. From this point it is supervised by an 
audio operator who is on hand to dub in commercial announcements 
or station breaks. 

The coaxial line from the relay receiver terminates in a video con- 
sole where it is under control of the video operator who also is on duty 
to dub in shots from the studio or film for commercials or station 


breaks or to switch over to a succeeding program. On a remote 
program without too much studio or film pickup the technical opera- 
tion can be handled by four technicians: the technical supervisor, 
the audio operator, the video operator, and the transmitter operator. 

With the facilities described, WBKB has handled, by remote 
pickups, a range of subject matter which is fairly representative of 
the great possibilities open to television through this type of opera- 
tion. Some of the subjects covered to date have been: baseball, 

Fig. 5 Station master-control room, co-ordination point for remote and studio 


basketball, hockey, ice follies, boxing, wrestling, billiards, water polo, 
Museum of Science and Industry events, stock exhibitions, golf 
tournaments, football, a circus, and automobile racing. This list 
probably will be expanded manyfold in the months and years to 
come. It offers an engaging example of the horizons opened to the 
television receiver viewer through this remarkable medium, television 
remote operation. 


(1) Abraham, L. G., and Romnes, H. I., "Television network facilities," 
Elec. Eng., p. 477; May, 1947. 

(2) W. J. Poch and J. P. Taylor, "Microwave equipment for television relay 
service," Broadcast News, p. 20; October, 1946. 

Sound Motion Pictures for 
Passenger Trains* 



Summary This paper discusses the practicability of converting existing 
railway dining cars for the presentation of motion pictures as a medium for 
relaxation while still retaining the use of the car for restaurant service. 
Determining factors for selecting available 16-mm standard projection 
equipment are given, and problems presented by the moving train with re- 
spect to good screen results are outlined. Necessary modifications to stand- 
ard equipment are described and details regarding a rigid demountable 
screen and an adequate loudspeaker system are given. The large power 
capacity of the car's battery system, in conjunction with the General Electric 
Amplidyne converter, is used to operate the complete motion picture installa- 
tion. The paper concludes with statements regarding the final results ob- 
tained, passenger comments received, and the general public reaction to the 
installation made for the Chesapeake and Ohio Railway. 

THE POSTWAR plans of many industries have led the public to 
expect unique developments. In line with this thought, the 
Chesapeake and Ohio Railway Compay decided, among other innova- 
tions, to present motion pictures as a form of relaxation to passengers 
on their de luxe passenger trains. The long backlog in the railroad- 
car building program has delayed the building of a special theater 
car. Instead, it was decided to convert existing dining cars for the 
dual purpose of showing full-length feature films and still retain the 
use of the car for restaurant service. 

The 60-foot twin-unit diner car, The George Washington, was 
selected and brought to the Huntington, West Virginia shops for 
necessary modifications. A major change had to be made to the 
sixteen dining-car tables. Retracting-lever mounts fastened to the 
under side of the table tops enabled the tables to fold in a vertical 
position against the side walls, clearing the floor area for occupancy. 
A total of 343 square feet of floor area provided for fifty chairs and a 
two-foot aisle for through traffic. The remainder of the car space 
was utilized for housing air-conditioning equipment, food com- 
partments, supply lockers, and a miniature projection room measur- 
ing 45 inches wide and 70 inches long. The air-conditioning system 
was piped to operate inside the projection booth, in addition to an air 
* Presented April 21, 1947, at the SMPE Convention in Chicago. 




duct and exhaust for the lamphouses and comfort of the projectionist. 
For continuous performance, dual 16-mm projectors were installed. 
Small booth dimensions made it necessary to select a left- and a 
right-hand type of projection equipment. This combination oc- 
cupied a minimum of space and enabled the projectionist to be cen- 
trally located, facing the operating side of each projector. The type 
of equipment selected was the new RCA Model PG-201 and the 
Natco Model 3015. Professionally designed, both of these models lent 

Fig. 1 General view of diner, showing passengers seated for presentation. 

themselves suitably for this particular installation. Strictly alternat- 
ing current in operation, the constant-speed motors maintain correct 
sound speed within 1 per cent even when line- voltage change is 10 per 
cent. The amplifier output level rated at +35 decibels proved ample 
for overcoming extraneous noise level of the train in motion. Shock- 
mounting the amplifiers in their respective machines was necessary 
to prevent damage to the tubes and components from car vibration. 
The projector mechanisms had to be rigidly mounted on solid 
bases, which in turn were welded to the car frame for absolute rigidity. 
Steady screen performance was realized only when the above 

66 BITEL January 

precaution was observed even when riding over rough areas of road 
bed. The same precautions had to be taken with the screen proper. 
Here the problem was twofold, for the screen had to be rigid and still 
be easily demountable. The picture size was determined to clear 
the heads of persons occupying the first row of seats. The height 
clearance of 55 inches for a seated person allowed for a screen image 
41 inches by 55 inches. A four-inch lens with a throw of 48 feet 
gave the desired dimensions. Beaded screen fabric, cemented to a 
3 / 4 -inch plywood backing, properly masked and equipped with snap- 
hinge hardware, enabled quick mounting of the screen in its proper 
place. Two rod braces fitting into keyhole sockets lock the screen 
rigidly in position. 

Finger-tip control of all switches, mounted in one unit between the 
two projectors, facilitates ease of operation of the equipment. Stand- 
ard projection-room practice of change-over is accomplished with a 
change-over switch, which automatically applies a glow voltage to the 
projection lamp on the incoming machine when the motor switch is 
tripped on the first cue. Full voltage is applied by tripping the light 
change-over switch on the final cue, at the same time cutting off 
the lamp current on the outgoing machine. By adjusting proper 
glow voltage to the 750-watt projection lamps and operating within 
the time element of the two film change-over cues, a clean change- 
over of light is accomplished. Sound change-over is simultaneously 
accomplished by simply switching the outputs of the respective am- 
plifiers and placing a dummy load across the outgoing machine. 

Preliminary tests with the existing heavy layers of car insulation, 
previously installed in conjunction with the air-conditioning system, 
proved valuable in reducing the outside noise level to a negligible 
degree. Heavy drapes and carpeting served admirably in correcting 
the acoustic condition of the car. The narrow and long dimensions 
of the dining car presented a problem of good sound distribution. 
A beaming effect proved to be the answer. A two-way speaker sys- 
tem is used, although no dividing network is used. The RCA MI- 
6304 driver unit, coupled to the Altec-Lansing Model 808 multi- 
cellular horn, and a standard 10-inch permanent-magnet speaker 
make up the desired combination. The cone speaker simply supplies 
the tonal balance for the upper cellular unit, which beams the sound 
the full length of the car. 

A 32-volt, direct-current 1000-ampere-hour battery, in conjunction 
with a 5-kilowatt General Electric Amplidyne inverter supplying 


substantially constant 110-volt alternating current, constitutes the 
power system. The General Electric inverter, Model 5LY153A1, the 
Amplidyne Booster Inverter which is series-connected with the ampli- 
dyne that bucks or boosts the voltage supplied by the axle generator 
or battery to maintain constant alternating voltage and frequency 
on the output side of the inverter, is essential for correct sound speed 
operation of the projection equipment while the train is in motion or 
standing at a station. The unusually large capacity of the inverter 
serves well on peak loads, such as change-over periods, and for opera- 
ting auxiliary equipment requiring 110 volts alternating current. 
The inverter is approximately 45 inches long by 16 inches in diameter 
and weighs 800 pounds. An adequate cradle support is built beneath 
the car structure to house the complete unit. 

The final results were very gratifying, and met with warm reception 
from the general public. The inaugural run from Washington to 
Cincinnati was attended mostly by officials of the company, film 
critics, editors, and representatives of trade journals. Their reaction, 
comments, and reception were very glowing in their praise. As one 
observer stated, "It is a curious sensation at first, to watch a film and 
have the theater jostle gently. But the consciousness of motion 
soon fades. True, when the camera moves up for a scene, that action 
plus the forward motion of the train brings a feeling of accelerated 
speed, and when the camera backs away for a long shot, you may feel 
as if you're going in two directions at once, but most of us found the 
experience rather unique. The sound comes across with exceptional 
clarity. After a few moments, the movement of the train is forgotten 
and the story runs quite as smoothly as it does in your local theater." 

Succeeding runs proved so popular with the passengers that five 
additional diners were converted, and a special tavern theater is now 
being built. 


MR. WOODSON: Does the screen impede the passage of people through the 

MR. W. R. ISOM: The people are sealed to one side of the car and the passage 
aisle is on the other side. In that way people can- pass without interfering 'with 
the showing of the film. 

MR. DAWL: How many shows an evening are given? 

MR. ISOM: The full length picture runs an hour and fifteen minutes, so I would 
imagine that they run it as long as there is an audience. 

MR. DAWL: Was the voltage of the light taken from alternating- or direct- 
current side? 

MR. ISOM: I assume it was taken off of the alternating-current side. 

Improved Film Splicer 1 



Summary A waterproof tape splicer for the assembly of motion picture 
film prior to development is described and illustrated. 

IN SEARCHING for improvement in film splicing which would reduce 
waste, increase durability and strength of splices, and be simple to 
accomplish under darkroom conditions, an improved film splicer was 
designed, constructed, and put into operation by the Twentieth 

Fig. 1 

* Presented April 22, 1947, at the SMPE Convention hi Chicago. 




Century-Fox film laboratory. This splicing machine utilizes a dur- 
able waterproof cloth tape. 

Fig. 2 

Fig. 1 shows the splicer ready for operation. The various parts of 
the apparatus have been numbered, in this photograph only, for easy 
reference. In Fig. 2, the two ends of film to be spliced are placed in 
the film guides, properly positioned over the pins 7 and 15 with the 
ends hanging over the chute 5, and the clamps 8 and 14 are locked 
down holding the film firmly in position. 




In Fig. 3, the lever 11 is pulled downward shearing the film ends 
at the cutting edges 2 and 12 and allowing the clippings to drop down 
through the chute 5. 

Fig. 3 

In Fig. 4, the lever 11 is raised to its original position, the lever 6 
is moved from right to left bringing the film-guide platforms and 
edges 2 together which gives a solid roof over chute 5 and by this 
movement of lever 6 the plungers 3 are automatically raised causing 
the film ends to be swung into a vertical position. The end 10 of 




adhesive tape 10 is then pressed by finger against drum 13 and lever 
13 is shoved forward rotating drum 13 slightly which brings sufficient 
tape forward so that it can be grasped more easily by the fingers and 
pulled forward across the platform as shown. 

Fig. 4 

In Fig. 5, lever 1 is pushed downward which releases the plungers 
5, allowing them to retract downward and the film ends to drop down 
on the tape. The end of the tape is then manually folded over the 
film as shown and lever 11 is pulled down forcing the cutting edges 9 
to shear the tape. 




In Fig. 6, the tape end just sheared is manually folded back across 
the film and lever 11 is brought down on the completed splice and 
pressure is applied to force good contact between the tape and the 
film. After clamps 8 and 1 4 are lifted the film can then be removed 
from the splicer. 

Fig. 5 

With this type of splice the film under extreme tension will tear 
anywhere except at the splice. This splice itself will last for a long 
period of time under constant processing conditions. 




CHAIRMAN C. E. FILLIMORE: How far along in the laboratory processes is 
this splicer used and where is it removed? 

Fig. 6 

MR. E. A. BERTRAM: This type of splicer is used on the friction-type developing 
machine, and the splice is made at the loading table and the film. After the splice 
is made at the loading table, it goes through the usual linear process and the 
developing machine is removed at the end of the take-off table and the rolls 
come out in individual sizes. If it is a 40-foot roll it would be split at that point, 
or a 1000-foot roll would be split at that point. It is nothing more than a method 
of attaching the two pieces together, perforating the film, and putting a piece of 
stickum over it and holding it so it will go through. 

AL New Sound Slidefilm Projector* 



Summary Sound slidefilm equipment is an audio-visual aid that is 
rapidly assuming its proper place in the fields of education, sales, and enter- . 
tainment. This type of equipment fills in the gap between silent still pic- 
tures and sound-on-film moving pictures. The purpose of this paper is to 
describe the design and construction of the EXPLAINETTE " 100", a sound 
slidefilm unit that has been built with a functional approach to the general 
application of such equipment. 

THE ELECTRICAL components of the EXPLAINETTE "100" can 
be broken down into: (1) the sound-reproducing unit consisting 
of the phonograph pickup, the sound amplifier, and the loudspeaker; 
(2) the phonograph motor; and (3) the slidefilm projector. 

The sound-reproducing unit consists of a crystal pickup feeding a 
small audio amplifier which in turn drives a 4- X 6-inch elliptical loud- 
speaker. The crystal pickup cartridge is a high-output unit that is fed 
into the grid of a beam-power output tube through an attenuating and 
equalizing network. The cartridge is mounted in a special arm so 
pivoted above the record that a 16-inch transcription can be played 
without tracking difficulty even though the arm measures only 7 1 /2 
inches from pivot to needle. 

The network between the pickup and the amplifier, besides giving 
control of volume, also is arranged to give a rising high-frequency 
response as the volume is increased. This was done on the premise 
that as the size of the audience increased and more volume was needed, 
an accentuation of the higher frequencies would improve intelligi- 
bility by overriding background noise and counteracting high-fre- 
quency absorption. 

The amplifier is an alternating-direct-current model utilizing a 
50B5 miniature output tube supplied with plate and screen voltage 
from a 35W4 half -wave rectifier. This selection of tubes was utilized 
because of their small size and also because of their ready availability 
for replacement in the field. 

The 4- X 6-inch elliptical speaker used was carefully designed so 
* Presented April 21, 1947, at the SMPE Convention in Chicago. 




that the proper cone and cone treatment were incorporated to assure 
clear sound in the speech-frequency range. All tests were conducted 
using the actual baffle in which production units are mounted so that 
the combination of baffle and speaker would do the job required. 

The record-rotating medium selected for this unit is a sturdy yet 
light-in- weight phonograph motor rotating at 33 Vs revolutions per 
minute. It has a gear reduction that is fully enclosed with the gears 
running in an oil bath. The motor is fan-cooled and the fan besides 
cooling the phonograph motor also agitates the air in the amplifier 
housing. The motor is rubber-mounted to the phonograph plate 
and the turntable and record are completely separated from the motor 
by a rubber sleeve that acts as 
a combination drive washer and 
insulator. This combination re- 
duces both rumble and feedback. 

The projector for this equip- 
ment is a specially designed unit 
constructed so as to become an 
integral part of the machine. 
The light from the 100-watt T8- 
type projector bulb is collected 
by a three-lens condenser system 
and heat-ray filter to provide 
uniform illumination of the 
single-frame aperture. 

The film as it passes through 
the aperture is held flat by 
aperture glasses. The rear plate 

of this pair of glasses is retractable and synchronized in motion 
with the film-advance sprocket and index mechanism. The objec- 
tive lens is mounted in a barrel that is friction-retained for ease in 
bringing the picture in focus on the screen. The objective lens is a 
3-inch focal-length lens and gives a brilliant picture on the self-con- 
tained screen for desk or table use and also at a distance of about 16 
feet. . 

The film-advance sprocket is provided with a friction clutch so that 
when the advance knob is pressed in the indexing cam is released and 
the picture may be brought into frame in the aperture. 

An elevating mechanism of the nut-and-screw type is provided to 
allow vertical positioning of the picture on the screen. 

Fig. 1 




The ventilation of the lamphouse is of the natural gravity type, but 
the flow of air is so directed that even after long periods of operation 
the film temperature in the aperture does not rise above 150 degrees 

Contacts with users of slidefilm equipment and the answers to- a 
questionnaire indicated that the one almost universal difficulty was 
that of threading of the film through the projector. Operators could 

Fig. 2 

not close the gate over the sprocket and keep the film in place until the 
gate was closed. The result was torn and punctured film and a 
frustrated operator while he fumbled through several attempts to get 
the film started properly through the aperture and over the sprocket. 

The answer to this difficulty was the development of a hinged 
film guide over the sprocket. This guide can be swung back away 
from the sprocket, the film positioned over the sprocket and the guide 
placed against the film without any danger of the film getting out of 
place when the lens barrel is closed. This improvement eliminates 
the possibility of damaged film entirely and greatly simplifies the job 
of threading the projector. 


SHELDON DICKINSON, 59, for twenty years Director of 
^ the Conservation Department of the Motion Picture Associa- 
tion, died Saturday, October 25, in Santa Monica, California, after 
a long illness. 

Mr. Dickinson had retired last July, ending a career that began 
in 1912 in the states rights phase of the motion picture industry. 
He was connected with a number of motion picture companies in the 
following fifteen years before joining the Motion Picture Producers 
and Distributors of America, forerunner of the Motion Picture As- 
sociation, in 1927. As Director of Conservation of the MPA, he 
handled technical matters for the motion picture industry, which in- 
cluded contacts with the Society of Motion Picture Engineers, 
National Film Carriers, Inc., National Fire Protection Association, 
and the National Board of Fire Underwriters. He devised a plan 
for film exchange fire inspection which established safety records 
for all major companies in the handling of motion picture films. 
This method of inspection gave to the motion picture industry 
one of the finest safety records of any major industry. 

Mr. Dickinson was born in Chattanooga, Tennessee, in 1888, and 
studied engineering at the Georgia School of Technology. He was 
well equipped, therefore, to handle technical matters for the MPA 
and also to be a Fellow of the SMPE. He served for many years as 
a Member of the Board of Governors and also was formerly Finan- 
cial Vice-President of the SMPE. 

We shall remember him as one who was generous and tolerant 
toward his fellow man, and we shall remember his deliberate and 
slow delivery of counsel. 











771IGHT-HUNDRED members of the Society of Motion Picture Engi- 
/y neers and guests registered during the 62nd Semiannual Con- 
vention of the Society, which was held on October 20 to 24, 
1947, at the Hotel Pennsylvania, in New York City. The Get- 
Together luncheon on Monday was attended by two hundred and 
twenty-five members and guests, and there were three hundred and 
twenty at the Wednesday night Banquet. President Ryder presided 
at both of these functions and introduced those seated at the 
Speakers' tables. Judge Edward C. Maguire, Co-ordinator of the 
Motion Picture Industry of the City of New York, was the guest 
speaker at the luncheon. At the Banquet, the Progress Medal was 
awarded to Dr. John G. Frayne; the first annual Samuel L. Warner 
Memorial Award was presented to Mr. John A. Maurer; the 1947 
JOURNAL Award was given to Dr. Albert Rose; and thirteen Active 
members of the Society were elevated to the Fellow grade. 

For the first time in the history of the Society, A Theater Engi- 
neering Session was a part of the general program. There were ten 
of these sessions and three technical sessions. Another innovation of 
this Convention was the holding of an exhibit, at which there were 
thirty-five exhibitors. At the Television session and demonstration 
of large-screen television, over four hundred and fifty were in 


Mr. William C. Kunzmann, Convention Vice-President, and Mr. 
James Frank, Jr., were largely responsible for the great success of 
this Convention. Mr. Robert T. Kenworthy, who was in charge of 
the Exhibit; Mr. Gordon A. Chambers, who secured the many fine 
technical papers; Mr. Leonard Satz, who was responsible for the 
Theater Engineering papers; and the chairmen of all of the other 
Convention Committees worked hard to make this meeting such an 
outstanding success. Mr. Kunzmann, in addition to his many other 
activities, obtained passes to six of the first-run motion picture 
theaters in New York. Through the efforts of Mr. Harry B. Braun, 
an excellent public-address system was installed. Publicity was 
handled by Mr. Leonard Bidwell and Mr. Don C. Gillette most 

Theater owners, purchasing agents, and architects, who had not 
previously attended Conventions of the Society, were very much in 

The papers presented at this meeting will be published in early 
issues of the JOURNAL. These have not as yet been scheduled, but 
it is anticipated that the first of them will appear in the February 
















THE BANQUET held on October 22, 1947, during the 62nd 
Semiannual Convention of the Society, Dr. John G .Frayne 
was presented with the 1947 Progress Medal Award, given for out- 
standing achievement in motion picture technology. Dr. Frayne 
was chairman of the Progress Committee from 1932 to 1938; chair- 
man of the Pacific Coast Section for 1941 and 1942; member of the 
Board of Governors for 1946 and 1947; and at present is chairman 
of the Sound Committee. 

Born in Wexford, Ireland, in 1894, he received his early education 
in the Irish National School system. He was graduated from Ripon 
College in Wisconsin in 1917 and received a graduate scholarship 
at the University of Minnesota the same year. After serving in the 
Army during World War I and later as an engineer with the Ameri- 
can Telephone and Telegraph Company, he returned to Minnesota 
where he received the Ph.D. degree in physics in 1922. 

Dr. Frayne was a member of the faculty at the University of Min- 
nesota, professor of physics at Antioch College, and a National 
Research Fellow at the California Institute of Technology. For the 
past eighteen years he has been with the Electrical Research Prod- 
ucts Division of the Western Electric Company in Hollywood, 
where, at the present time, he is development supervisor. 

Since 1932, Dr. Frayne has been the author or coauthor of twelve 
papers published in the JOURNAL, for one of which he received the 
1940 SMPE JOURNAL Award. 


Among Dr. Frayne's technical contributions, the following are 

Investigation of reproduced sound-film print noise as a function of negative 
and print density, in the development of variable-density noise reduction. 

Original investigation of light valve, phototube, and printer gammas, and 
establishment of relationships for their optimum use. 

Research in sensitometric control of variable-density sound tracks which evolved 
into adoption of dynamic gamma control in their exposure, processing, and re- 
production. Accompanying this investigation and important in establishing the 
benefits to be derived from it was his intensive educational program among the 
studios and film laboratories. 

Development of the R A- 11 00 Integrating Sphere Densitometer, which virtually 
is a primary standard in the industry. 

Coauthor of the intermodulation method of testing and controlling processing 
and sound equipment which is now universally employed in control of variable- 
density recording. 

Investigation of sprocket-hole modulation. 

Studies and applications of light valves. Actively participated in the applica- 
tion of MGM four-ribbon light-valve push-pull development and, more recently, 
development of the current three-ribbon light-valve modulator. 

Active supervision of development of sound-film movements which are now 
standard and outstanding in their simplicity and performance. 

Development of a frequency-modulated control track for release prints. 

Supervision and development of several improved recording and reproducing 
optical systems. 

Contributions to the field of anticipated noise reduction. 

Development and supervision of new variable-area light-valve-type modulators. 

In addition to his technical achievements and the documenting 
of his work, Dr. Frayne has contributed in a broader sense by his 
sincere interest in the field of education and by his inspiration to his 
fellow engineers. An indication of the esteem in which he is held by 
the Society is given by the unanimous proposal that he be awarded 
the 1947 Progress Medal. 









FIRST annual Samuel L. Warner Memorial Award, for the 
^ most outstanding work in the field of motion picture engineer- 
ing, was presented to Mr. John A. Maurer during the Banquet held 
on October 22, 1947. This Award consists of a gold medal and an 
accompanying bronze replica, and it was established by the Warner 
brothers in memory of their brother, Samuel. It was fitting that 
the first recipient of this Award should be a farsighted pioneer in 
his field, in much the same way that Mr. Warner was in his. As 
Mr. Warner had faith in the value of the talking picture, so Mr. 
Maurer staked his ; udgment and his career on the usefulness of the 
16-mm sound-recording medium. 

One of the first engineers to appreciate the need for high quality 
in 16-mm sound recording and reproduction, Mr. Maurer has dedi- 
cated his career to furthering this objective. Not only has he pro- 
moted this cause by manufacturing equipment of his own design, 
but he has given unselfishly of his time and ability to assist in every 
way possible to improve 16-mm sound quality. 

Mr. Maurer started his work by the design of the first precision 
16-mm camera and sound-recording devices to reach the commer- 
cial market. In order to provide a specialized laboratory service 
to the users of 16-mm equipment, he collaborated in the establish- 
ment of a motion picture laboratory where 16-mm film could receive 
the necessary treatment to ensure excellence of results. 


When, during the War, the Armed Services asked for the co- 
operation of the Society and that of the American Standards Asso- 
ciation in the preparation of a large number of War Standards in 
the fields of both 35-mm and 16-mm motion pictures, Mr. Maurer 
was one of the first members of the Society to be drafted for this 
work. Throughout the War, he gave liberally of his time to this 
project, and his extensive background of experimental activity was 
the source of much useful information to the committees. 

His outstanding contribution was the design and construction of 
special film-recording machines for the manufacture of 16-mm test 
films to complement the standards which he had helped to prepare. 
A series of test films was prepared to provide a means of testing any 
16-mm sound equipment then or now in use. These films, which are 
available through the Society of Motion Picture Engineers and the 
Motion Picture Research Council, provide the tools whereby the 
engineers of the industry can test their equipment and evaluate their 

Mr. Maurer was appointed to serve out an unexpired term as 
Engineering Vice-President in 1945, and was elected in 1946 to serve 
a two-year term in this same capacity. During his tenure of office, 
the work of the Standards Committee, for which he, as Engineering 
Vice-President, is responsible, has gone forward steadily. 

The industry owes a debt of gratitude to Mr. Maurer, who has 
made available to it equipment, methods, processes, test films, and 
above all, an inspired leadership, to bring 16-mm sound films to the 
point where they compare favorably with the 35-mm films with 
which the industry leads the world. 










xnoR HIS PAPER on "A Unified Approach to the Performance of 
1 Photographic Film, Television Pickup Tubes, and the Human 
Eye/' which was judged to be the most outstanding paper originally 
published in the JOURNAL during 1946, Dr. Albert Rose was pre- 
sented the JOURNAL Award at the 62nd Semiannual Banquet. 

Dr. Rose was graduated from Cornell University in 1931, and re- 
ceived his doctorate from there in 1935. That same year he accepted 
a position in the research laboratory of the electron- tube plant of the 
Radio Corporation of America in Harrison, N. J. The work at 
Harrison was dedicated to the development of a pickup tube that 
would provide greater light-sensitivity contrast and picture quality, 
and would require less space in the camera than the iconoscope. 
He conceived the idea for the orthicon camera tube, forerunner of 
the image-orthicon television picture tube which was developed by 
Dr. Rose in collaboration with other members of the RCA Labora- 
tories staff. It was for his work on the image-orthicon tube that 
Dr. Rose received the 1946 Morris Liebmann Memorial Prize from 
The Institute of Radio Engineers. 

In 1943 the image orthicon was turned over to the Army for use 
in guided missiles. Because of military security restrictions, it was 
not made available for commercial television until after the end of 
the war. 

Dr. Rose is a member of the American Physical Society, The Insti- 
tute of Radio Engineers, and Sigma Xi. 


ACTIVE members of the Society of Motion Picture 
^ Engineers were elevated to the Fellow grade at the Banquet 
held on October 22, 1947. The names of the recipients and the 
citations are listed below. 

F. E. ALTMAN, Eastman Kodak Company, 
"for original work in the field of optics of 
era and projection lenses." 


A. C. BLANEY, RCA Victor, 

"who has done much of the research and de- 
velopment work on the problem of photo- 
graphically recording sound on film." 

KARL BRENKERT, SR./ Brenkert Light Projec- 
tion Company, 

"for his work on the design, construction, and 
distribution of 35-mm projection lamps and 

DURING 1946 




*A Qnificct Approach, to trhe IPcfforrncinc^- of"* 

Photographic Film,, Television 3?icU~upTubc 

and the Human Eye" 

Albert" Rose 


P. E. BRIGANDI, RKO Radio Pictures, 

"who has been responsible for development 
work in sound recording. 

C. C. DASH, Eastman Kodak Company, 

"for the design and manufacture of motor- 
generator sets used extensively in the motion 
picture industry." 

A. J. HATCH, Strong Electric Corporation, 

"who has been responsible for development 
work on projection lamps." 

R. KlNGSLAKE, Eastman Kodak Company, 
"for his work on the design of the camera and 
projection optics." 

R. G. LlNDERMAN, Mole-Richardson Company, 
"who has been responsible for the design and 
construction of studio lighting equipment and 
is considered one of the top specialists in this 

R. H. TALBOT, Eastman Kodak Company, 
"who has been responsible for much research 
and development work on the physical be- 
haviorism of motion picture film and who has 
contributed several papers to the JOURNAL." 

M. G. TOWNSLEY, Bell and Ho well Company, 
"who has contributed to the design and con- 
struction of 16-mm projection equipment, 35- 
mm printing equipment, cameras, and ac- 

FORDYCE TUTTLE, Eastman Kodak Company, 
"who has been responsible for the design and 
construction of 16-mm cameras and projec- 
tors and was in charge of highly specialized 
development of various types of equipment 
during the war." 

R. T. VAN NIMAN, Motiograph Corporation, 
"who has been responsible for the design of 
35-mm motion picture projectors." 

R. J. ZAVESKY, National Carbon Company, 
"for much of the development work on carbon- 
arc lighting and who has contributed many 
papers to the JOURNAL." 

Society of 

Motion Picture Engineers 


Atlantic Coast 

Chairman Secretary-Treasurer 

William H. Rivers Edward Schmidt 

Eastman Kodak Co. E. I. du Pont de Nemours & Co. 

342 Madison Ave. 350 Fifth Ave. 

New York 17, N. Y. New York 1, N. Y. 


Chairman Secretary-Treasurer 

R. T. Van Niman George W. Colburn 

Motiograph George W. Colburn Laboratory 

4431 W. Lake St. 164 N. Wacker Dr. 

Chicago 24, 111. Chicago 6, 111. 

Pacific Coast 

Chairman Secretary-Treasurer 

S. P. Solow G. R. Crane 

Consolidated Film Industries 212 24 St. 

959 Seward Santa Monica, Calif. 
Hollywood, Calif. 

Student Chapter 
University of Southern Calfornia 

Chairman Secretary-Treasurer 

Thomas Gavey John Barnwell 

1046 N. Ridgewood PL University of Southern 

Hollywood 38, Calif. California 

Los Angeles, Calif. 

Office Staff New York 


Boyce Nemec Margaret C. Kelly 


Thomas F. Lo Giudice Helen M. Stote 

Dorothy Johnson Beatrice Melican 

Helen Long Silvya Morrow 



TOSEPH A. DUBRAY, who joined the Society of Motion Picture 
*J Engineers in 1928 and was elected a Fellow in 1934, resigned his 
membership in the Society early last year because of ill health. He 
also retired from Bell and Howell, with whom he had been associ- 
ated since 1929, and has gone to live near Paris. 

In 1898 he started experimenting with motion picture photogra- 
phy and in 1905 he became active in this field. During World War I 
he was associated with the Pathe Company in Paris where he did 
experimental work with moving pictures. After the war, he came 
to the United States where he was employed by several different 
motion picture companies before he resigned to do free-lance 
photography and to perfect the technical aspects of his work. 

With the advent of sound motion pictures, Mr. Dubray joined 
the Bell and Howell company. He was placed in charge of the 
Hollywood office and later was sent to Europe to organize company 
interests in the motion picture industry there. Upon his return, he 
was in charge of the Professional Equipment Division of the company. 

Mr. Dubray was very active in the affairs of the Society and 
served on the following committees: Admissions; ASA Sectional 
Committee on Motion Pictures, Z22; Historical and Museum; 
Journal Award; Laboratory Practice; Membership and Subscrip- 
tion; Papers; Progress; Standards and Nomenclature; and 
Standards. He was a Manager of the Pacific Coast Section in 1933; 
a Manager of the Midwest Section in 1939, and Chairman during 

Mr. Dubray was the author or coauthor of nine papers published 
in the JOURNAL, and made important contributions in the fields of 
printing and perforating. 



ITTENRY PHELPS GAGE, vice-president of the Society of Motion 
JLJL Picture Engineers from 1927 through 1930, retired from active 
duty at the Corning Glass Works on July 1, 1947. 

Dr. Gage was born on October 4, 1886, at Ithaca, New York. 
He was graduated from Cornell University in 1908 and received 
the Ph.D. degree in physics from there in 1911. His postgraduate 
years were devoted to the study of arc lamps and color problems. 
At this time he made some of the engineering experiments and 
researches recorded in "Optic Projection", published in 1914 and 
written in collaboration with his father, Simon Henry Gage. In 
this book, one chapter is devoted to the projection of motion pic- 

In 1911, Dr. Gage joined the Optical Laboratory of the Corning 
Glass Works, where he specialized in the design of pressed signal 
lenses and the development and standardization of signal colors for 
use by the railroads. These laboratory studies have since been 
enlarged to include some phases of illuminating engineering, as well 
as colored glasses for scientific, industrial, and theatrical purposes. 
Two of the products developed are the corrugated "CONZA" con- 
denser for motion picture projection and the two "black-light" 
glasses. One of these, opaque to the visible and transparent to the 
ultraviolet, is used for spectacular scenic effects with fluorescent 
materials and also in some advanced types of sound recording. The 
other is opaque to visible rays and transparent to infrared or "heat 
rays". Both had important military applications. 

Dr. Gage has presented nineteen papers before the Society of 
Motion Picture Engineers and other technical societies, and has 
published five in the TRANSACTIONS and the JOURNAL of the SMPE. 



Preparations for the Spring Meeting of the Society which will be held at the 
Santa Monica Biltmore Hotel, May 17 to 21, inclusive, are now under way. 

Authors desiring to submit papers for presentation at this meeting are requested 
to obtain Authors' Forms from the Vice-Chairman of the Papers Committee 
nearest them. The following are the names and addresses: 


250 West 57 St. 4431 West Lake St. 6706 Santa Monica Blvd. 

New York 19, N. Y. Chicago 24, Illinois Hollywood 38, Calif. 

P. O. Drawer 279 

Montreal, Que., Canada 

The Author's Form together with an abstract not exceeding 200 words should 
be submitted to Mr. N. L. Simmons, at the address above, not later than April 15, 
1948. The abstract should be suitable for use in preparation of the program. 

Two manuscript copies of the paper, at least one of them complete with illus- 
trations, should be sent to Mr. Simmons not later than May 1, 1948. 

In order that the preliminary program may be printed and distributed to the 
members not later than May 1, it is important that all abstracts and Authors' 
Forms for this meeting be received by April 15 for inclusion on the program. 


The officers, Board of Directors and member companies of the newly recon- 
stituted Motion Picture Research Council, which was described in the JOURNAL 
for October, 1947, are listed below. 


Y. FRANK FREEMAN, Chairman of the Board 
THOMAS T. MOULTON, Vice-Chairman of the Board 
WALLACE V. WOLFE, President 
R. A. KLUNE, Vice-President 
WILLIAM F. KELLEY, Secretary-Treasurer 

Board of Directors 





Member Companies 

Columbia Paramount Hal Roach 

Samuel Goldwyn Republic 20th Century-Fox 

Metro-Goldwyn-Mayer RKO-Radio Universal-International 

Warner Brothers 




le September 11, 1947, meeting of the Midwest Section opened with the show- 
ing of a Kodachrome short as an example of a sound track made locally. 

The first part of the program consisted of the reading by Robert E. Lewis of two 
papers: "Design and Operation of Trace Recording Camera", by Robert E. 
Lewis and Seichi Okubo, of the Armour Research Foundation; and "Use of G-3 
Film Processing Tank", by Robert E. Lewis and Henry Froula, of the Armour 
Research Foundation. 

The recording camera was analyzed in terms of a review of the problems rather 
than any novelty of design. It was recommended that high-intensity, blue phos- 
phor tubes be used when possible. 

Formulas for the use of the G-3 tank were distributed. There was a short dis- 
cussion of the problems presented by the confinement of chemical activity. 

The paper by Howard C. Hardy, "The Psychological and Physical Factors Be- 
hind Acoustical Design", dealt with basic considerations and their practical 
application. The use of a stethoscope or other probe was reviewed as a means of 
locating noise sources. A good discussion was had concerning gear noise, panel 
vibration, and dipole radiations. 

One hundred members and guests attended the October 9 regular monthly 
meeting of the Midwest Section held in the rooms of the Western Society of En- 
gineers in Chicago. Lee de Forest, now associated with American Television 
Laboratories, Inc., of Chicago, presented an interesting historical discourse en- 
titled "Early Days of Sound on Film". He outlined his early work in the optical 
recording of sound on film and mentioned the numerous difficulties which beset 
the pioneers in this field. Not the least of these was the one of convincing a too- 
complacent film industry that talking pictures would have a commercial future. 
Technical and artistic problems involved in recording and reproducing sound films 
were overcome, one by one, to the end that commercially acceptable sound films 
were publicly shown in New York theaters several years before the industry gen- 
erally accepted the idea of having synchronized sound and music with its pictures. 
In the discussion following his talk, Dr. de Forest expressed doubt that television 
in theaters will be of any great importance, except for certain specialized events, 
because of programming difficulties, but stated that he feels that the future of the 
industry is already assured by the public acceptance of television as a home enter- 
tainment medium. 

The second paper of the evening, "Producing Films for Schools", was presented 
by Ellsworth C. Dent, General Sales Manager of Coronet Instructional Films and 
Educational Director of Coronet magazine. Mr. Dent discussed in considerable 
detail the problems and procedures involved in making films which will convey the 
desired information in a manner both intelligible and acceptable to the student- 
age groups for which the films are intended. He stressed the value of color films in 
making the presentations more interesting and natural. At the conclusion of his 
talk, Mr. Dent exhibited a recently completed Coronet film, "Shy Guy", intended 
for showing to high-school-age groups, which treats the problem of students who 
do not know how to get along with other students, and effectively shows them how 
to go about improving their relations with others. 


* * * * 

On November 13, 1947, there was a meeting of the Midwest Section at the 
Ansco Laboratories in Chicago, 111. Chairman A. Shapiro presided and intro- 
duced the newly elected officers of the Section for the coming year, and Haldon 
A. Leedy of the Armour Research Foundation presented a paper on "Magnetic 
Sound for 8-Mm Motion Pictures". Dr. Leedy gave a brief history of magnetic 
recording illustrating his talk with slides. One of these showed the relative space 
available for the sound record on 35- , 16- , and 8-mm film. The space avail- 
able for 8-mm film is 0.030 inch wide and may be placed on either edge of the 
film. All film demonstrated used the area between the sprocket holes and the 
edge of the film. 

An Ampro 8-mm projector, mounted on a base containing the amplifier and 
film-stabilization mechanism developed by Armour, was used hi making demon- 
strations. A loop running in the projector was recorded and played back im- 
mediately on the same system. An 8-mm Kodachrome reduction print with 
recorded voice and musical background was presented, in which the music and 
the intelligibility of the voice were good. 

Before the discussion, Chairman Shapiro warned that it would be a mistake 
to overemphasize the addition of soundheads to existing equipment, since 8-mm 
models should be redesigned completely. The discussion brought out the follow- 
ing points: 5000 cycles per second would be difficult to record and is not to be 
expected in the near future; three speeds are now being used for experimenta- 
tion 16, 18, and 24 frames per second; the magnetic material is particles of iron 
oxide, about one micron in size, and especially heat-treated. The response of 
the system at 18 frames per second is flat from 100 cycles to about 2500 per second 
with sharp cutoff. 

James Wassell of Ansco welcomed some 300 members of the Society and their 
guests to the Laboratory, and William Macomber, manager of the Laboratory, 
gave a brief description of its scope of operations. A short demonstration reel 
of Ansco Color 16-mm film was shown, and a tour of the Laboratory concluded 
the meeting. 

Membership and Journal Subscriptions 

Recently the Los Angeles Better Business Bureau informed President 
Ryder that an unauthorized group in the Hawaiian Islands was soliciting 
Christmas memberships in the Society of Motion Picture Engineers. The 
Bureau believes that these people are collecting initiation fees or member- 
ship dues which probably will not be forwarded to the Society. 

Legitimate subscription agencies are authorized by the Society to accept 
Journal subscriptions and they will continue to handle these as in the past. 
However, no arrangements have been made for them to handle memberships. 

All checks or money orders should be made payable to the Society of 
Motion Picture Engineers, Inc. 


Membership Directory 

In the Spring of 1948 the Society of Motion Picture Engineers will 
publish a Membership Directory containing the names and addresses of 
all members. Questionnaire cards were enclosed with the dues bills sent 
to the membership early in January, and members were requested to return 
them without delay. If you have not sent in your card, please do so now. 

1. Fill in the card promptly. 

2. Return it with your dues bill and remittance. 

3. Print or typewrite. 

4. If you make any change in address or position after you have sent 

in your card, inform the SMPE immediately so that you may be 
correctly listed. 

The Editor 

Training-Film Research Project 

Sponsored by the Navy Department, a research project is under way at Penn- 
sylvania State College to increase the value of training films. The study is 
intended to develop principles of producing effective sound films that provide 
"complete" instruction in the shortest possible time. 

Types and characteristics of training films already produced will be analyzed 
and evaluated. Appropriateness of subject matter in terms of its application to 
real situations will be studied. Individual response to sound-film training will 
also be investigated, to determine speed of learning and retention of memory. 

Based on collected information and new research findings, a highly selected 
and specialized library and information center will be established. These services 
will be available for use of the Navy and other government departments. 

The project at Penn State, under the direction of Dr. C. R. Carpenter, pro- 
fessor of psychology, will be conducted in close co-operation with other univer- 
sities and government agencies engaged in similar work. 

Library and Search Service 

The American Library Service has announced that it specializes in books, 
periodicals, and other material relating to the motion picture industry. This 
organization provides a library and search service free of charge. 

Through the libraries and research departments of motion picture studios, the 
American Academy of Motion Picture Arts and Sciences, the Library of Congress, 
and other sources, it locates and makes available scarce and out-of-print books 
and periodicals. Requests for single titles or complete collections should be 
addressed to American Library Service, 117 West 48 Street, New York 19, N. Y. 
They will also supply a listing of available scarce material, on request. 


The editors present for convenient reference a list of articles dealing with sub- 
jects cognate to motion picture engineering published in a number of selected 
journals. Photostatic or microfilm copies of articles in magazines that are avail- 
able may be obtained from The Library of Congress, Washington, D. C., or from 
the New York Public Library, New York, N. Y., at prevailing rates. 

American Cinematographer 

28, 10 (Oct., 1947) 
Future of Cinematography (p. 358) 

Historical Development of Sound 

Films. Pt. 4 (p. 362) 


The S.E.I. Exposure Meter (p. 370) 
Telefilm Sets 16-Mm Program for 

Production Distribution (p. 376) 
New Exposure Meter Developed by 

G. E. (p. 379) 

28, 11 (Nov., 1947) 
Mitchell Background Projector 

(p. 391) 
30 Years of Technicolor (p. 392) 

The Men Behind the Mouse. Pt. 2. 

How Animated Cartoons are Made 

(p. 394) H. A. LIGHTMAN 
Motion Picture Art Direction 

(p. 396) H. HERMAN 
Historical Development of Sound 

Films. Pt. 5 (p. 398) E. I. 

The Cinema Workshop. 17. Sound 

Cutting and Recording (p. 400) 

Blue Seal Cine Devices 35-Mm 

Sound Recorder (p. 404) 
Akers Professional Conversion for 

the 16-Mm Bolex Camera (p. 406) 

British Kinematography 

11, 4 (Oct., 1947) 
Colour Modified Compact Source 

Lamps for Film and Television 

(p. 107) H. K. BOURNE and 

The Production of Cartoon Films 

(p. 117) D. HAND 
The British Tricolour Camera 

(p. 123) J. H. COOTE 


20, 11 (Nov., 1947) 
Console for Dubbing (p. 142) 
International Photographer 

19, 10 (Oct., 1947) 
What the Cameraman Means to Ad- 
vertising Photography (p. 8) 
International Projectionist 

22, 10 (Oct., 1947) 
B. & L.'s New 40-Inch Photographic- 
Lens Stops 'Em (p. 18) 
Acoustics. Pt. II. Sound Level 

Meter (p. 22) 

New Cadmium-Mercury Lamp Bows 
in Studios (p. 23) 

22, 11 (Nov., 1947) 
Color Temperature: Origin and 

Meaning (p. 5) W. W. LOZIER 
The Production of Cartoon Films 

(p. 10) D. HAND 

Projection Data Charts. VII. Pro- 
jection Room Accessories Data 
(p. 12) R. A. MITCHELL 
British Screen Brightness Standards 

(p. 18) 
The Triatic Signal Tracer (p. 22) 

Why Acetate Film? (p. 25) 

RCA Review 

8, 3 (Sept., 1947) 
Colorimetry in Television (p. 427) 


Application of I.C.I. Color System to 

Development of All-Sulfide White 

Television Screen (p. 554) 


Radio News (General Interest Section) 

38, 6 (Dec., 1947) 

The Recording and Reproduction of 
Sound. Pt. 10 (p. 48) O. READ 


of the 

Society of Motion Pictnre Engineers 



Theater Television ^A General Analysis 


New Developments in Mercury Lamps for Studio Lighting .... 

F. E. CARLSON 122 

Acoustical Factors in the Design of Motion Picture Equipment . 


A Modern Sound-Reinforcement System for Theaters 


An Improved Intermodulation Measuring System 


Elimination of the Fire Hazard of Projectors Using Nitrate 

63rd Semiannual Convention. 177 

Society Announcements. ! 178 

ASA Appointment 182 

Inter-Society Color Council 183 

International Commision on Illumination 185 

Sections 188 

Staff.. 188 


Chairman Editor Chairman 

Board of Editors Papers Committee 

Subscription to nonmembers, $10.00 per annum; to members, $6.25 per annum, included in 
their annual membership dues; single copies, $1.25. Order from the Society's general office. 
A discount of ten per cent is allowed to accredited agencies on orders for subscriptions and 
single copies. Published monthly at Easton, Pa., by the Society of Motion Picture Engineers, 
Inc. Publication Office, 20th & Northampton Sts., Easton, Pa. General and Editorial Office, 
342 Madison Ave., New York 17, N. Y. Entered as second-class matter January 15, 1930. 
at the Post Office at Easton, Pa. under the Act of March 3, 1879. 

Copyrighted, 1948, by the Society of Motion Picture Engineers, Inc. Permission to republish 
material from the JOURNAL must be obtained in writing from the General Office of the Society. 
The Society is not responsible for statements of authors or contributors. 

Society of 

Motion Picture Engineers 

342 MADISON AVENUE NEW YORK 17, N. Y. TEL. Mu 2-2185 




Loren L. Ryder Clyde R. Keith 

5451 Marathon St. 233 Broadway 

Hollywood 38, Calif. - New York 7, N. Y. 


Donald E. Hyndman William C. Kunzmann 

342 Madison Ave. Box 6087 

New York 17, N. Y. Cleveland, Ohio 


Earl I. Sponable G. T. Lorance 

460 West 54 St. 63 Bedford Rd. 

New York 19, N. Y. Pleasantville, N. Y. 



John A. Maurer James Frank, Jr. 

37-0131 St. 18 Cameron PL 

Long Island City 1, N. Y. New Rochelle, N. Y. 


Ralph B. Austrian 
247 Park Ave. 
New York 17, N. Y. 



John W. Boyle Robert M. Corbin Charles R. Daily 

1207 N. Mansfield Ave. 343 State St. 5451 Marathon St. 

Hollywood 38, Calif. Rochester 4, N. Y. Hollywood 38, Calif. 

David B. Joy Hollis W. Moyse 

30 E. 42 St. 6656 Santa Monica Blvd. 

New York 17, N. Y. Hollywood, Calif. 


William H. Rivers S. P. Solow 

342 Madison Ave. 959 Seward 

New York 17, N. Y. Hollywood, Calif. 


Alan W. Cook Gordon E. Sawyer 

4 Druid PI. 857 N. Martel 

Binghampton, N. Y. Hollywood, Calif. 

Paul J. Larsen 

Los Alamos Laboratory R. T. Van Niman 

Lloyd T. Goldsmith University of California 4431 W. Lake St. 

Burbank, Calif. Albuquerque, N. M. Chicago, 111. 

Section Chairmen and Secretary-Treasurers listed on page 188. 
Office Staff listed on page 188. 

Theater Television 
A General Analysis * 




Summary Excellent engineering progress has been made in the de- 
velopment of equipment and methods for the exhibition of television pictures 
in theaters. Considerable thought has. been devoted to types of acceptable 
programs for theater television. However, the final design of commercial 
television equipment for theaters is not yet available, nor are proved and 
acceptable program methods as yet clearly defined. 

Accordingly, theater television may be regarded at present as being, in 
some respects, in a partly developed state. Considering this situation, the 
following analysis is perforce a descriptive report, as of today. It contains 
as well some analytical discussions of possible future trends. But the data 
and conclusions are of necessity subject to revision as further progress in 
theater television brings forth new methods and offers greater capabilities in 
this highly interesting field. 


TELEVISION PICTURES in theaters will, initially at least, have the 
strong appeal of novelty. Accordingly, the screen pictures may 
be smaller than those shown from projected motion picture film in 
the same theater. Since, in any case, a sqreen having a specially 
desirable directional characteristic will be used, the problem of 
masking thus will be automatically solved by a screen change be- 
tween motion picture presentations and television projection. The 
directional characteristics of the television screen will also be dis- 
cussed below. Even if an intermediate-film process, as described 
below, is used, the presumably lesser detail or resolution of the 
television pictures will justify a smaller screen image than for 
motion picture projection. 

Since motion pictures in most theaters range from 9 X 12 feet to 
18 X 24 feet, television pictures may fall within the range of 6 X 8 
feet to 15 X 20 feet. Ultimately, it may be found desirable and 
economical to use identical picture sizes for television and motion, 
pictures, but at present this seems unnecessary. 

The picture masking may be made slightly different for television. 
It is permissible to mask off more of the corners of the picture in 
* Presented October 21, 1947, at the SMPE Convention in New York. 


96 GOLDSMITH February 

television, a step which is justified since the television pictures may 
fall off in resolution more rapidly, toward the corners, than do the 
projected motion pictures. 

The light which forms a projected television picture (without inter- 
mediate-film recording) is produced in a cathode-ray tube by special 
electrical methods. It is a costly form of illumination and should be 
conserved to the utmost and utilized efficiently. For this reason 
unusually high-speed television projection systems are used (of the 
so-called Schmidt-optics type) with speeds as high as //0.6 v to//0.8. 
Further, a screen is preferably used which will throw light only to 
those portions of the house which are occupied by the audience. 
After all, any of the precious light which is thrown to the ceiling or 
off to the side walls of the house is wasted. It might better be 
utilized by concentrating all light reflected by the screen in the locali- 
ties occupied by the audience. The directional screens may, there- 
fore, be specially .suited to the design of the theater, giving a con- 
siderable central concentration in long, narrow houses and a wider 
horizontal spread in shallow and broad houses. Vertically, light will 
similarly be concentrated between the top balcony and the front of the 
orchestra. While directional screens have been used to some extent 
for motion picture projection, the television directional screens will 
likely be even more specially "tailored" to the particular theater. 

In the front rows of some theaters, the line structure of the tele- 
vision image occasionally may be visible, particularly with imperfect 
interlacing. This is not a particularly serious defect, as has been 
shown by the satisfactory experience in this regard in receiving tele- 
vision broadcast pictures in the home. In any case, it is possible that 
slight residual optical aberrations may sufficiently soften television 
pictures so that the line structure is not noticeable in practice. 

The television engineer and the exhibitor alike must strike a 
thoughtful balance between television picture size and the corres- 
pounding brightness. If the picture size is increased 50 per cent, the 
picture brightness will of course drop to less than 50 per cent. The 
motion picture field has experienced a continual urge toward larger 
and brighter pictures. In some theaters, -brightness has been 
sacrified for size, with much resulting inconvenience to the audience 
when finding its way in a too dimly illuminated house. For this 
reason, it is thought that television pictures may well sacrifice some- 
thing of their size for the sake of acceptable brightness. 

Picture weave was quite noticeable in the early days of the motion 


picture but now it is not a serious factor unless badly worn film is used 
in decrepit projectors. In television, picture weave is rather unusual, 
and should not be noticeable under normal projection conditions. 

If a large and less-bright television picture is adopted in a given 
theater, it may prove necessary to change the house lighting before 
going over to a television presentation. That is, the residual house 
lights may be dimmed further whenever television is about to be 
shown. As previously suggested, this is not a particularly desirable 
procedure since it imposes extra duties on the house staff, requires 
added control equipment for the lights, and may inconvenience the 
entering or leaving audience during the period of dimmed illumina- 
tion. It is unlikely that this step will be necessary except perhaps 
in the early days of theater television in color where the problem of 
screen illumination is even more pressing because of certain technical 
and psychological factors. 


As previously indicated, the picture brightness will depend to 
some extent on the skillful adaptation of the directional screen to the 
particular theater in which the picture is shown. Obviously, theater 
television will require close co-ordination between the television 
engineer, the architect, and the exhibitor. This, however, is a 
desirable state of affairs for motion picture exhibition as well. 

Present-day motion pictures have a usual screen brightness of about 
10 foot-lamberts. Television pictures, even in the early stages of 
the art, should show the same brightness or, preferably, 25 to 50 
per cent higher brightness. This may require acceptance of a 
somewhat smaller picture in monochrome. For color presentations, 
picture size might require still further reduction in the early stages of 
that art. 

Television pictures should show no marked falling off in brightness 
toward the edges and corners. The skillful optical design of the 
projection system has enabled meeting this requirement. Unfor- 
tunately some motion picture projectors have been so designed (or 
used) that the brightness at the center of the picture is undesirably 
higher than that at the edges of the picture. If an intermediate- 
film process is used for television presentations this factor will 
require consideration in connection with the suitability of the pro- 
jector itself. 

It is well known that defects in an optical system, namely the so- 

98 GOLDSMITH February 

called optical aberrations, result in a loss of contrast, or decrease in 
gradation range in the viewed picture. Whereas a "brilliant" or 
"sparkling" picture may have a gradation range between 50-to-l 
and 200-to-l, a "flat" picture may have a range of only 10-to-l or 
even 20-to-l. 

Scattered light in an imperfectly designed projection system will 
contribute to lack of picture contrast. So, also, will certain halation 
effects in the television projection tube. These last have recently 
been overcome in large measure by the process of aluminizing the 
fluorescent surface. 

However, special care should be taken in the design of television 
optics and the selection of television pictures to maintain an accept- 
able contrast in the projection picture. This will also require a 
certain amount of careful maintenance of the optical system to reduce 
undesired and parasitic reflections. 

The "whiteness" of the television picture presents an interesting 
topic, for opticians and colorimetric experts. At present no standard 
has been generally adopted to control the "whiteness" of either tele- 
vision or motion pictures. Indeed, change in the illuminant or arc- 
type in motion pictures gives rise to marked changes in the tint or 
"whiteness" of the projected picture. 

Fortunately, the human eye easily adapts itself and regards most 
light tints, when sufficiently bright, as "white". Thus, after a 
moment or two, the eye will regard a light yellow, a light yellow-green, 
or a pale blue as "white". % 

Nevertheless, if there is any marked difference between the color 
of the projected motion picture and the color of the television pic- 
ture, this may be detrimental to the audience reaction to one or the 
other of these. It would be well to keep television pictures and 
motion pictures in monochrome at approximately the same "white" 
tint. This tint may, however, vary for different theaters. If a 
rather yellowish arc is used in a theater having an old and yellowed 
screen, a blue-white television picture will show up that situation. 

It would be quite appropriate for the Society of Motion Picture 
Engineers to study the standardization of "whiteness" for theater- 
television pictures. At a later date American Standards may be 
correspondingly developed. 


The picture detail, or resolution, adopted for theater-television 
practice should be a reasonable compromise between extremely 


high detail (and correspondingly high cost of specialized equipment 
and precise operation) on the one hand, and insufficient "story- 
telling" capabilities or undue softness of the pictures, on the other. 
If the subject matter is presented with sufficient clarity so that but 
few complaints, if any, are received from the theater audience when 
television pictures are displayed, it is certain that an acceptable 
value of picture resolution has been adopted. 

Motion pictures in theaters have a theoretical resolution of between 
1000 and 1500 "lines". (These are "television lines", and represent 
twice the resolution value expressed according to ordinary photo- 
graphic or motion picture practice.) Television pictures usually 
will not require, in the early stages of commercial exploitation, as 
high detail as the motion picture itself. The 525-line pictures now 
broadcast probably will be acceptable. Appreciable improvement 
would result only from substantial increases such as going to approxi- 
mately 800 or approximately 1200 lines. Such a change does not 
seem economically or otherwise justified at present. 

There is room for good showmanship in television presentations 
in order to avoid any obvious or objectionable transition from the 
high resolution of motion pictures to the somewhat lower practicable 
resolution for television pictures. One way of handling this would be 
to produce a short film which would precede the television presenta- 
tion. This film might state that the next part of the program would 
be television and point out some of the dramatic or other attractive 
aspects of the impending television performance. The film in ques- 
tion might start with material photographed as sharply as standard 
motion picture practice normally requires. During this film the 
resolution might be reduced gradually (preferably by diffusion means) 
until the resolution at the end of the film, just before the television 
presentation, was approximately the equal of that of the television 
picture, or even slightly less. Another short film or trailer might 
follow the television presentation, preceding the next motion picture. 
This film might be recorded with a "resolution transition" going from 
television resolution to motion picture resolution. Doubtless other 
methods of bridging the television-to-motion-picture transition can 
be devised. 

There is one major argument in favor of using the current tele- 
vision-broadcast resolution value for theater presentations. If 
theaters are to be able to use broadcasts of transcendentally impor- 
tant events which are broadcast by television (as may be desirable, 

100 GOLDSMITH February 

say at elections, conventions, certain sports events, and the like), it 
would be somewhat complicated for the theater to have to use 525- 
line television reproduction for such events and then to switch over 
to some other and higher number of lines for other television program 
material syndicated to the theater. Such a switch-over is by no 
means impossible, but it is an added complication, probably unjusti- 
fied in the early stage of the art. 

While the picture resolution will undoubtedly fall off toward the 
edges and corners, just as it does in motion picture reproduction, yet 
the change should not be obtrusively noticeable. This is not an 
unduly difficult requirement. 


Two of the main methods for reproducing television programs on 
theater screens will be discussed briefly, together with a summary 
of their apparent present-day advantages and limitations. 

(a) The first of these is cathode-ray-tube projection systems, 
usually using Schmidt optics or some high-speed projection-lens 

Such a system has numerous advantages. It reproduces the 
program instantaneously as received, a factor of psychological im- 
portance. It is free from the cost of expendable materials, such as 
photographic film. Inasmuch as a high-power arc is not used, the cost 
of electric power probably will be lower in such a system. There is 
no processing cost for film involved in this process. Nor is there any 
possible loss in picture quality or resolution (nor, on the other hand, 
a possible improvement in adapting the gamma characteristics of the 
picture to the television system) as a result of photographic recording, 
processing, and projection. Gaps or jumps in the program, resulting 
from the time required for film processing, are absent. Accordingly, 
the program continuity or flow is more readily obtained. 

The system has certain limitations including the following: High- 
speed optics generally require either that they be designed for a 
specific throw which is convenient in the theater or, alternatively, 
that the equipment be installed at the position required by the de- 
signed throw, even if that location be inconvenient. If television 
projectors are to be placed in the projection room, they will require 
additional space and may, therefore, lead to structural changes and 
building reinforcements. Further, television projectors are unlike 
motion picture projectors, and accordingly the theater staff will 


require retraining to utilize such equipment. In addition, the optical 
and electrical systems in such projectors must be cleaned and in- 
spected systematically to ensure effective operation, and according 
to methods not at present familiar to the theater staff. Since tele- 
vision projectors use optical and electrical equipment, as do motion 
picture projectors, it is conceivable that certain questions of juris- 
diction will arise in labor circles. And, finally, when direct projection 
of television programs takes place, no film record exists and therefore 
there is no available means for repeating the program at some con- 
venient, desirable, or prearranged time (except by retransmitting it 
from a film record or from a repeated live-talent performance at the 
point of program origination). 

(b) According to the second method of theater television, the 
incoming program is reproduced on a bright cathode-ray tube, but 
the image is projected, not on the theater screen, but on motion pic- 
ture film in a recording camera. The film is rapidly processed in 
special high-temperature rapid-flow processing systems and is then 
projected from the theater projectors (with or without modification 
of these projectors) according to the usual motion picture technique. 

The advantages of such a system include the following. So far as 
projection is concerned it uses the normal and well-understood motion 
picture projector. It does not become necessary to train the pro- 
jectionist on a new method of projection (although he or some other 
other worker will, of course, be required to understand how to use 
the television receiver, the recording camera, and the film-processing 
equipment). The picture which is projected readily can be as bright 
as that normally shown in the theater, of the same size, and of the 
usual color or " whiteness". Further, the entire television material 
can be rerun as desired for later shows and at any convenient time. 
Thus it fits into the motion picture program with considerable flexi- 
bility. Some thought will, nevertheless, be required in connection 
with abuse of this system in sports events, such as horse racing, where 
gambling is usual and picture delays may lead to certain abuses. 

Among the limitations of the film-recording process for theater 
television are the following: There is, as stated, a slight delay (from 
a fraction of a minute to several minutes) between the 'actual time o 
occurrence of the program and its reproduction in the theater.. 
Change-over from motion picture programs to television. programs 
will require considerable dexterity in the use of the available pro- 
jectors. If 16-mm film is used, with resultant lower cost, different 

102 GOLDSMITH February 

projectors will be needed. If 35-mm film is used, its cost will become 
a factor of some importance. Further, the expense of handling and 
processing the film must be considered. In this connection it should 
be remembered that undoubtedly only acetate-base film would be 
acceptable for theater recording of television programs. 

Other limitations involve the need for liquids for processing, heaters, 
driers, winding and film-transport equipment, and other associated 
gear. Questions may arise as to jurisdiction between cameramen 
and projectionists in processes of this sort. The projection room 
may also present space and facilities problems in connection with the 
installation of the necessary supply of water, clean air, power sup- 
plies, and the like. 

(c) Other processes are known for theater-television presentation. 
One of these is the so-called Eidophore method which, so far as is known, 
has not been demonstrated in the United States. This Swiss 
method is one of considerable novelty and ingenuity, but its perform- 
ance under practical operating conditions is not known at this time. 


There will be discussed briefly the advantages and limitations of 
five possible locations of the television projection equipment in a 
theater. Assuming available space and facilities, the projection 
room itself seems at first to be the desired location, provided again 
that efficient television-projection systems can be built for the corre- 
sponding throw. If film recording is used, the projection problem 
probably presents few difficulties. 

(a) A first possible location for the television-projection equip- 
ment is behind the translucent screen, with the picture projected on 
the screen toward the audience. One advantage of this system is 
that no space is required in any part of the theater other than back 
stage, nor need any structural modifications be made anywhere else 
in the theater (except as required for interconnecting wiring). If the 
projector were mounted at a height equal to that of the center of 
the screen, keystoning will also be absent. 

There are, however, certain limitations to this location. For one 
thing, the necessary space for the required throw simply may not be 
available backstage behind any feasible location of the translucent 
screen. It is unlikely that complete flexibility of design and place- 
ment will exist in present-day theaters. Further, projection of this 
type will require, in most instances, a very wide-angle projection lens 


which will have a correspondingly low aperture or light-passing value. 
The cost of the elevated support for the projector (assuming no key- 
stoning), and the cost of the surrounding projection room, may be 
considerable. The efficiency of a translucent screen, even of a highly 
directional type, is generally considerably below that of an opaque 
screen. The out-of-the-way location of the television projector 
necessarily would require a duplicate operating staff except in the 
unlikely event that the entire television-projection .equipment could 
be accurately and simply controlled remotely from the projection 
room. Such remote control, however, doubtless would be costly 
and less than simple. 

(6) A second possible location for the projection equipment is 
either on or below the stage, or in the orchestra pit. In this case an 
opaque screen would be used with front projection. 

The advantages of such a plan include the absence of need for any 
modifications of the house either in the orchestra, balcony, or pro- 
jection room. Further, no seats need be removed from the house. 
It should be noted, however, that a rather special type of directional 
screen would be required for such a markedly oblique projection 

Among the difficulties to be expected in this case may be mentioned 
the following: Space may not be available either below stage or in 
the orchestra pit. Rather extensive structural changes might be 
required if such a location were used. The projectors necessarily 
would employ wide-angle optical systems because of their nearness 
to the screen, and such equipment usually is inefficient in the produc- 
tion of bright pictures. Serious keystoning might be anticipated and 
would require correction. Again a duplicate operating staff, or, alter- 
natively, remote control of the projection equipment, would be needed. 

(c) A third possible location for the television-projection equip- 
ment is somewhere in the central axis of the orchestra. 

Such a location has the advantages of offering considerable flexi- 
bility in the selection of the precise place at which the television 
projector is installed. Thus, this system is extremely well adapted to 
provide whatever throw is optically preferred and economically 
desirable. Further, no space in the projection room is needed nor 
yet any changes in the projection-room equipment (beyond control 
and interconnection circuits for signaling, and the like) . In addition 
to providing an adequate and selected throw, this location permits 
the ready use of a suitably directional opaque screen. 

104 GOLDSMITH February 

There are some limitations in a system of this* sort. It requires 
that certain seats in the orchestra be removed to make way for the 
projection equipment. Persons located behind the projector may 
experience difficulty in viewing the television picture pleasantly. 
The intrusion of operated equipment in the orchestra to some extent 
interferes with the desired theatrical "illusion of reality". The 
costs of wiring and certain related costs may be considerable for such 
a location since most theaters have been designed without any con- 
sideration of such a possible future need for space and facilities in the 
center of the orchestra. There will be some keystoning from pro- 
jection at orchestra level and this, in turn, will require correction. 
Since the projector light beam emanates from a point in the orchestra 
it may be visible, particularly in houses where smoking is permitted or 
where dusty conditions prevail. This factor may not be noticeable 
in other cases. In this system there will al&o be required two operat- 
ing staffs, one for motion pictures in the projection room and one for 
television in the orchestra television-projection location, again as- 
suming that remote control of television projectors is not feasible on 
an everyday basis. 

(d) A fourth conceivable location for the television-projection 
equipment is somewhere between the extreme front and the extreme 
back of the first or second balcony. 

Such a system has certain advantages. It does permit considerable 
flexibility in the location of the^equipment. It requires no added 
space or change in the projection room, excepting perhaps of minor 
nature. The important orchestral seats are left without any change 
or intrusion. As before, any desired type of opaque directional 
screen may be used. 

Among the difficulties which might be anticipated for such a 
location are the following: Certain of the balcony seats' must be 
removed and the view from certain other seats will be blocked (unless 
the television projectors are placed at the extreme back of one of the 
balconies). Undoubtedly strengthening of the balcony structure 
will be required in some instances; this may prove a costly and 
cumbersome undertaking. The achded expense of special wiring and 
certain related costs will be involved for balcony locations. The 
picture throw will in general be a long one, and this may not fit in 
with the best designs for current television projectors of the direct 
type. As in all other balcony locations, keystone correction will be 
needed. Assuming personal operation of the television projectors, 


70 operating staffs will be needed or their equivalent, with proper 
>rdination and intercommunication. 

(e) A fifth and final possible location for television projectors is in 
motion picture projection room itself. 

Such a location offers certain obvious and attractive advantages. 
For one thing it concentrates all projection equipment, of whatever 
nature, in one room. Similarly all wiring arid interconnection is 
hi the same room. Only a single operating staff is needed, al- 
though this staff may be a larger one ultimately than would be re- 
quired for motion picture projection alone. It is also simple to use 
film-recording systems for television presentation in the projection 
room itself since the" film projectors are close at hand. Indeed, 
wherever film recording is used (that is, the intermediate-film tele- 
vision-projection system), the projection room offers major advan- 
tages as a location. 

However, there are certain limitations to the projection-room loca- 
tion for television projection. The room size likely will require an 
increase, and this in turn will lead to considerable structural changes. 
The added weight of equipment will, in turn, demand other structural 
changes for strengthening the supporting members. Since a con- 
siderable added amount of electrical (or even film-processing) equip- 
ment will be placed in the projection room, care will be required to be 
certain that no novel physical or fire hazards are introduced. Unless 
the intermediate-jilm process is used for television, the long throw 
to the screen may not fit too well with presently available television- 
projection systems. And, as usual, keystone correction will be needed. 

From all of the preceding it can be seen that the desirable location 
in the case of any particular theater depends on whether the inter- 
mediate-film process or the direct-projection process is used for 
theater television and also upon the dimensions and physical con- 
struction of the particular theater and its projection room. Ob- 
viously no general prescription can be used which will be guaranteed 
to bring perfect health to television in every theater. 

As a matter of economy, convenience, and availability of staff 
training, it is probably best at this time to produce the sound accom- 
panying television programs directly from the motion picture ampli- 
fiers and stage loudspeakers. In effect, this amounts to introducing 
the received sound into the circuits associated with the sound-track 
output of the motion picture projector. 

106 GOLDSMITH February 

However, it may prove desirable to modify the frequency charac- 
teristic of the reproducing system when television programs are 
reproduced in order to secure the most natural and desirable quality 
of reproduction. 

Since change-overs from motion pictures to television and back 
again may become increasingly frequent, it will be necessary to have a 
simple and errorproof change-over system, presumably suitably inter- 
locked with the picture change-over system from motion pictures to 
television and back again. 


Large-screen color television has been demonstrated successfully. 
It is natural to inquire concerning the practicability of theater color 
television at this time. 

There are certain considerations that indicate that color television 
in theaters should be introduced after considerable experience has 
been gained in monochrome theater television and after further 
developments in color television have been carried out successfully. 

It must be remembered that, because of the use of color filters, 
color television requires considerably more light from the original 
projection tube or tubes or, alternatively, the acceptance of a smaller 
picture for identical brightness. While certain ingenious technical 
expedients enable this factor partly to be overcome, yet it is sure 
that the light-producing efficiency of color-television equipment is 
unlikely to equal, or even closely approach that of monochrome 
television equipment. 

Further, color television requires considerably more elaborate and 
costly apparatus. The radio or cable channels for program syndica- 
tion must transmit a far wider block of frequencies for color television 
than for monochrome, with correspondingly increased first cost and 
maintenance charges, or rentals as the case may be. Color-television 
equipment is also more complicated than monochrome equipment 
and mav require skilled handling and maintenance. 

In live-talent presentations, more studio illumination is required 
(or alternatively, a far more sensitive camera tube). In addition, 
careful consideration must be given to the color of the costumes, 
sets, make-up, and the like. All of these factors correspond to in- 
creased expenditure of time and funds. 

In the case of programs taken from film, similar difficulties arise. 
Color film is a precise product which, at this time at least, is in rela- 
tively short supply. Indeed, it is not known whether the existing or 


projected color-film manufacturing facilities would be capable of 
meeting the requirements of the television broadcast field were color 
television to be generally adopted. This condition may persist for 
many years, since the successful manufacture of color film is a 
difficult art of high precision. 

Color film is also far slower than monochrome film. This, in turn, 
would restrict the range of time and subjects which could be recorded 
for television purposes. 

In the theater itself, the intermediate-film process for television- 
program projection would require the availability of color film which 
would be of sufficient sensitiveness to enable photographing the 
incoming program in color, together with the capability of high- 
speed processing in the theater. So far as is known, color film which 
can be processed at high speed for such theater purposes is something 
for future accomplishment rather than present commercial availability. 

While the preceding considerations indicate that color television is 
not available for practical and commercial theater purposes at this 
time, and that exhibitors necessarily will confine their television 
presentations to monochrome, yet it should be mentioned that color 
television does offer attractive possibilities in the future. It can 
readily be agreed that color presentations are, in general, superior 
artistically and dramatically to black-and-white presentations. It is 
therefore hoped that, within the next decade or two, color television 
also may find its place in theaters. 


The major cost factors which must be considered by the exhibitor 
entering the field of theater television include the following. Some 
of these factors are major; others are relatively small. 

The first factor to be considered by the exhibitor is the making 
of a systematic survey of his theater and a study of appropriate meth- 
ods of introducing television into that theater. It would be a 
major error, in a new field of this sort, for an exhibitor to enter 
theater television uninformed as to its general characteristics and 
without data as to the most suitable way in which television equip- 
ment can be installed and operated in his own theater. Such surveys 
can be conducted by trained technical and program men who have 
been active in television. 

Following a survey, the exhibitor presumably will place an order 
for appropriate television equipment. The various results of this 

108 GOLDSMITH February 

analysis or survey will indicate the general nature of the equipment 
which he may select. Clearly, a small theater in a town of medium 
size will probably find a different solution advisable from a large 
theater in a great city. 

Following the selection of equipment, it becomes necessary to 
install such equipment in neat and reliable fashion. This is handled 
in much the same way as the sound motion picture equipment. 

Once installed, the equipment will require a certain amount of 
maintenance and servicing. This can be arranged with appropriate 
agencies or representatives of the equipment manufacturer. It is 
believed that modern television equipment for theaters will require 
only a reasonable amount of maintenance. 

Regardless of the type of television equipment which has been 
selected, the theater staff will require training in its daily use. The 
staff must further acquire skill in smoothly changing over from motion 
pictures to television and back again. The size of the staff which 
can handle both motion picture and television programs will require 
analysis, and perhaps some negotiation. 

The exhibitor of necessity must find an available source of tele- 
vision programs. He can hardly depend upon televison broadcasting 
for that purpose because of certain restrictions and also because the 
theater owner, in general, will desire exclusivity of use of his program 
materials in his own neighborhood. 

The programs to be shown by television may in part consist of 
film material which is sent from a central transmitting station to a 
group of subscribing theaters. The cost of such a service will of 
course depend upon the cost of the program and the cost of carrying 
it to each individual theater in flawless shape. 

Another portion of the television program in theaters may consist 
of live-talent presentations. Here again is a cost factor which will 
depend upon quality of the talent and performance, and the cost of 
carrying the program to each theater. 

The total cost of a program is, therefore, the sum of at least two 
elements, namely, the program cost itself, and that of carrying the 
program to the theater (that is, of syndicating it). It is possible 
that these elements will be combined into a single charge for the 
delivery of the program at the theater, in much the same way in 
which films carry a charge which includes actual delivery. 

It is clear that the greater the number of theaters which can use a 
given program at a particular time, the less may be the program cost 


per theater, and also the less may be the cost of carrying the program 
to the theater. Manifestly, if one thousand theaters seating an 
average of one thousand persons each utilize a television program 
simultaneously, the cost would be far less per theater (or per member 
of the audience) than if a small number of theaters of limited seating 
capacity were to carry the program at a given time. Here again 
we encounter the overwhelming advantages of large-scale syndication 
which, accordingly, presents a major problem, and also an oppor- 
tunity to the theater-television field. 

As against the factors of expense just listed (which might include 
special advertising of the television programs, adaptation of opera- 
tions to the insertion of television, and the like), there is the pleasant 
factor that box-office returns may be increased 'substantially because 
of the television presentations in the theater. In fact, theater income 
may be increased for at least two significant reasons. In the first 
place, a program containing attractive television material as well as 
motion pictures may command a higher admission price than a motion 
picture program alone. In the second place, if the house is more 
nearly filled for each performance because of the "pulling power" 
of television programs, the total number of persons entering the 
theater per day will be correspondingly increased. Only experience 
will show the extent to which these factors operate in practice under 
various conditions. Undoubtedly the size and type of theater, its 
location, the nature of the audience, the availability of competitive 
syndication facilities, and the like will determine the increase in 
theater revenue resulting from television and, accordingly, the 
appropriate scale or investment in television by the exhibitor as well 
as the program-originating agency. 


The problems of programming in theater television are, strictly 
speaking, not all outright engineering problems. They are, however, 
so closely tied in with the engineering techniques arid apparatus 
that it is appropriate briefly to refer to them at this point. 

It is of course evident that theater-television programs must fit 
into the schedule of motion picture presentations without awkward 
gaps or abrupt and undesirable changes of mood or subject matter. 
Accordingly, program planners will face the problem of fitting tele- 
vision and motion picture material into each complete show in such 
fashion as to form a unified and interesting performance. 

110 GOLDSMITH February 

However, when events of supreme importance occur, constituting 
"transcendental news events", it may be necessary to throw all every- 
day rules into the discard. In such an instance good showmanship 
might even involve interrupting everyday material to make way 
for something that is unique and of possibly tragic interest to the 
entire audience. It is to be hoped, for many reasons, that such 
events will not break into normal theater operations too frequently. 

A number of types of television programs suitable for theater 
presentation are fairly obvious of acceptance. Thus, news events 
will have real interest. So will sports events, or crucial parts of such 
sports events. It will be- quite a problem to fit the best parts of a 
baseball or football game, for example, into a theater presentation. 
The top events in a circus, or rodeo, being capable of prescheduling 
on an accurate basis, afford more flexibility and therefore more 
readily usable material. 

Live-talent shorts may be of real interest, particularly if the actors 
in them or the subject matter are related to the motion picture 
program in the same theaters. In that case, a live-talent presenta- 
tion might even function as a "supertrailer" for the motion picture 

Short subjects, comedy subjects, and "black-outs" all seem sus- 
ceptible of development for theater-television purposes. 

There are some legal matters that will require attention either 
by the exhibitor or by the organization that supplies him with tele- 
vision programs by whatever syndication means may be used. 
Undoubtedly copyrights will exist on the picture and sound (or 
speech) of practically every presentation, except news events. The 
rights of the copyright owners in music will require attention. Patent 
rights may be involved in equipment and circuits. And there may 
even be some rather interesting legal questions in connection with 
so-called "violation of the right to privacy" in such States as will 
not permit the public display of photographs of living persons or 
episodes in their lives without their previous permission. It may be 
mentioned that some States do not recognize this right to privacy 
while others do, thus complicating the situation in connection with 
the national syndication of news events. 


In a key city, there are usually theater chains controlling a con- 
siderable 'number of theaters, smaller theater groups, and individual 


theaters not affiliated with any larger group. When television pro- 
grams become available for syndication, methods will be required to 
sort out these various theaters in accordance with their television 
needs. Obviously the extremely large groups of major theaters 
might be able to afford their own television programs, syndicated 
exclusively to them and perhaps to a limited number of relatively 
noncompetitive independent theaters. Smaller groups of theaters 
likely will have to form a coalition among themselves, and with 
the probable addition of some independent theaters, to build up a 
group justifying a special syndication service. 

Each group of theaters, which has its own television programs and 
syndicates them to its members, necessarily will require central studios 
for live-talent production and a central projection room for film 
transmissions. However, several such syndicating agencies might 
readily rent (or own) studio space in a single building or group of 
buildings devoted to theater-television program production. 

On the physical side, the actual syndication of programs can be by 
one of the following methods : 

The simplest method, though perhaps not the most economical, 
involves the use of specially quiet telephone lines which are equalized 
to the extent necessary for excellent picture transmission and which 
have repeater stations sufficiently close together to prevent the in- 
trusion of "noise" into the picture. This system has the advantage 
of utilizing facilities which may be available but it does require some 
changes in wiring at the telephone exchanges and the addition- of con- 
siderable amplifying and equalizing equipment. The sound channel 
naturally presents no problem being practically identical with a high- 
quality standard broadcast circuit. 

Another method is to run a coaxial cable to the group of theaters 
which are to be served. Such cables also require repeaters and 
equalizers but are more specifically adapted to picture transmission. 
Both the cable and the telephone-line methods of syndication have 
the advantage of being strictly private which, from the theater view- 
point, is of course desirable. 

Another method which may well be quite economical is the use of 
highly directional or narrow radio beams to carry the program for 
syndication. The advantages of such a system may be economic, 
both as to fir^b cost and maintenance. If the beam is sufficiently 
narrow, is operated on a special frequency, and perhaps has some 
"secrecy" element in it, unauthorized pickup of the program may be 

112 GOLDSMITH February 

avoided as a practical proposition. It would be odd if, in the new 
theater-television art, we again encountered the old-fashioned motion 
picture "bicycling" of early days. If radio syndication is used, as 
described, it will be necessary that the government allocate, through 
the Federal Communications Commission, the necessary channels 
to enable such operation. Other physical problems will arise. 
Thus, some theaters might be shielded from the central transmission 
station and would then require an intermediate automatic radio- 
relay station located off to one side to avoid obstruction of the signal 
by the obstacle. Again, some theaters may find themselves in an 
"electrically noisy" location (that is, with much electrical interference 
with reception) . If so, highly directional receiving antennas, shield- 
ing, or other expedients may prove necessary. 

If radio syndication is used, a heavy-duty television receiver will 
be necessary in the theater to handle the picked-up program and to 
transfer it, by projection, to the screen. If wire or cable syndication 
is used, probably somewhat simpler receivers will be feasible. 


As has been suggested, the more widely distributed the individual 
television program, the more economic the operation. This would 
indicate that large-scale television-program producers will build up 
national syndication facilities of one sort or another. It cannot be 
stressed too strongly that quality of performances and economy of 
operation (in terms of program cost per member of the audience) 
depend considerably on national syndication). 

The principal types of interconnection of cities (and theaters) for 
national syndication are by coaxial cable or by radio-relay systems. 
A coaxial cable is really a hollow conducting pipe with an insulated 
central conductor running through it. A radio-relay system is a 
series of "booster" stations each of which picks up the incoming 
signal, amplifies it in one way or another, and sends it along in strength- 
ened form to the next "booster" station. This is a greatly over- 
simplified description in each case but sufficiently indicates the nature 
of the connection. 

In each case cities not lying directly on the network will require 
side-line or "spur" feeders to carry the program to them. Sometimes 
this may be a rather costly procedure as, for example, in the -far 

The economics of national syndication will depend, of course, upon 


the number of cities (and theaters) served by each national theater- 
television network. If a sufficiently large number of theaters (and 
members of the audience) are served by a network, the cost per 
member of the audience may be quite reasonable. 

Another factor in determining the practicability of a national 
theater-television network will be the number of hours per day that 
it may be in actual use. Once an elaborate cable or radio network is 
established, it is troublesome either to tear it down for other uses or 
even to switch it over to other uses from time to time. For reasons 
connected with good showmanship, such a network, in many in- 
stances, must be continuously in "readiness to serve". For this 
reason it probably will tax the showmanship and inventive ability 
of the television-program groups to keep national and even urban- 
syndication facilities in use to the desired extent. 

If radio facilities are used for syndication, it will again be necessary 
to assign appropriate frequencies for their operation, such authoriza- 
tion coming from the Federal Communications Commission. 

A number of other problems will arise in connection with national 
syndication. For one thing, there is a three-hour difference between 
Pacific Time and Eastern Time. It' may prove necessary to divide 
the country into time zones and to utilize syndication primarily 
within one (or two adjacent) time zones. ' Alternatively, recorded 
programs may be repeated one, two, or three hours later as desired. 

Although national syndication offers the best promise of markedly 
reducing the cost of television programs per member of the audience 
and therefore of improving theater-television program quality, it 
probably will be a delayed achievement because it is, after all, an 
extremely large-scale and costly operation involving substantial 
capital investment and operating costs. 


In the early days of theater television, the extreme novelty and 
mystery of such programs will attract the audience on a curiosity 
basis, if nothing else. It would be easy enough today to fill theaters, 
for a while, with audiences eager to see large-screen television of any 
reasonably acceptable technical quality, and almost irrespective of 
the nature of the program. 

Yet it will not be long before theater audiences will come to regard 
television programs in the theater as just another sort of picture in 
motion, though not a motion picture. After all, the picture will 

114 GOLDSMITH February 

appear on the screen with its accompanying sound in much the same 
way as do the film presentations. When that day comes, television 
programs will be accepted mainly on their intrinsic quality. That is, 
the originality and dramatic or comic interest of the program will 
determine audience acceptability. 

Accordingly, those who produce television programs for theater 
use must, through ingenuity and good showmanship, discover those 
things which television can do particularly rapidly, convincingly, with 
human appeal, and with convenience. Only in this way can tele- 
vision programs assume a position of importance beside motion pic- 
ture material in the theater. 

As previously stated, news and sports events, and happenings of 
major importance will afford certain program material. But personal 
and live-talent presentation of a special nature will possibly be of 
considerable interest. Television programs will always depend for 
their appeal, in part at least, on "immediacy" (also referred to as 
"instantaneity" or "simultaneity"). Television is particularly ca- 
pable in the realm of permitting events to unfold, so to speak. That 
is, wherever the outcome is unknown and unknowable, television can 
present material of peculiarly appealing human interest. For this 
reason, it is likely that the techniques of theater television ancl of 
motion pictures in theaters will run along parallel rather than con- 
verging paths. And it is well that each should remain a different 
and distinctive type of theater entertainment. 

It is certain that other, as yet undisclosed and amazingly attractive, 
technical and program possibilities exist in the theater-television 
field. The engineers and showmen of the future are indeed offered 
a major opportunity to develop a new and important art. 


Exhibitors might naturally inquire what, at this time, would be a 
suitable procedure for them so that they may be prepared advan- 
tageously to enter the theater-television field and may take all such 
steps as shall make likely their success in that field. 

The present owners of theaters will be well advised to insist that 
their group representatives study the field of theater television, 
through committees or otherwise, and report back to the theater 
owners. It would be well if the theater owners were periodically to 
receive bulletins or reports descriptive of the technical, commercial, 
and program status of theater television. Since the individual 


theater owner will be unable to accumulate such information in his 
available time, the task should, as indicated, be delegated to ex- 
hibitor organizations. 

Present theater owners would also do well to install television- 
broadcast receivers in their homes or in their private offices in the 
theater. They should systematically follow local television-broad- 
cast programs so that they may see how that art is developing. Some 
of the television programs may be, in the exhibitor's opinion, "good 
theater", others may not. By becoming acquainted with television 
in this fashion, the' theater owner will have a better idea of what can 
be accomplished with television and may develop his own thoughts 
and proposals as to future and desirable types of programs for theater 

The exhibitor should also keep in touch with the technical societies, 
and notably the Society of Motion Picture Engineers, so that he 
may receive copies of any pertinent reports, or papers appearing in 
the JOURNAL OF THE SMPE. He should also follow the development 
of theater television in the trade press and should as well subscribe 
to the magazines dealing with television itself along broadcast lines. 
In this way he will know more about program structure, commercial 
problems, and the general development of television. 

Even more concretely, the present exhibitor should study the 
possible television installations in his own theater. On the basis of 
the material in the present analysis, he should keep in touch with 
manufacturers of theater-television equipment and in due course, 
secure their advice and estimates on installation of suitable equip- 
ment whenever they have announced publicly the availability of such 
apparatus. This, however, may not be for several years. Before 
doing this, however, it would be well for the exhibitor to confer with a 
competent architect acquainted with theater design so that any 
installation problems -may be analytically considered. Only in this 
fashion can the exhibitor know what he is doing and how to do it 
with least expenditure and with maximum results. 

The exhibitor should also keep in close touch with those groups 
which plan to offer television programs in his vicinity. In this way 
he will know when such programs will be available and at approxi- 
mately what cost. He will also be in a position to study the most 
efficient ways of introducing them into the motion picture program in 
his theater and will be prepared to devise a box-office schedule which 
will yield corresponding returns. 

116 GOLDSMITH February 

Persons who plan to enter the motion picture and television- 
theater field as owners should carry out a similar program to that 
just mentioned. They should affiliate themselves with well-informed 
groups who will render informational reports on the status and 
trends in theater television. In view of the complexities of theater 
design, and of recent important advances in that field, the prospective 
owner should be certain that his engineer and architect are alike 
well qualified. In this connection it must be stressed that the design 
of a theater for both motion pictures and television requires excellent 
engineering guidance both from the consulting engineer dealing with 
the theater owner and from the manufacturer of the equipment in 
question. Only with such information will the theater owner be 
likely to secure from his architect designs which will prove practical 
and economical in operation. In this connection it may be men- 
tioned that, considering the possible rapid rate of the development 
of both motion pictures and television in theaters, the design of future 
theaters should be far more flexible than in the past. Time limita- 
tions forbid mentioning the various details that are here involved. 

In summary, all exhibitors, present and future, should study, 
discuss, and understand television equipment, operations, programs, 
and economics. They should keep in touch with sources of depend- 
able information in these fields and should endeavor to draw their 
own conclusions systematically as the art develops. 


The Society of Motion Picture Engineers, as the leading technical 
group in the world in the motion picture field, is under the obligation 
of studying theater television, of assisting in its development, and of 
disseminating useful technical and operating information to all who 
may be benefited by such data. The Society is interested in the 
video-audio arts, and theater television is an important addition -to 
that group. Further, the utilization of film in theater television 
clearly brings it within the professional purview of the Society. It 
may be mentioned, as a fortunate and encouraging circumstance, that 
the relationships between the Society and The Institute of Radio 
Engineers, its sister organization, have been and remain cordial and 
co-operative. The Institute has been vigorously active in the develop- 
ment of basic television methods involved, as these are, in the com- 
munications and electronics field. In view of this, it is desirable, and 
to be expected that the Society of Motion Picture Engineers and The 


Institute of Radio Engineers will closely co-operate from time to time 
in standardization problems and in all other matters which will be 
mutually beneficial. 

Returning to the functions of the Society, it should arrange for 
the presentation before its membership and exhibitors of papers on 
theater television and, in fact,. on the use of film or photographic 
methods in the television field. It should arrange for the preparation 
of appropriate recommended practices in the field of theater television, 
these later to become generally accepted standards. In such activities 
it should collaborate with its sister societies. It should at all times 
endeavor to raise the level of performance of television and film 
equipment utilized for public-exhibition purposes in theaters and 
should widely disseminate accumulated information in its fields. 

It is also normal that the Society should represent the motion 
picture industry in its technical aspects, and in particular in relation 
to standards, channels, or facilities required for the syndication of 
theater-television programs, and all related matters. To that effect, 
it should secure industry opinion and thereafter represent that 
opinion before the Federal Communications Commission. It should 
continue its representation on the Radio Technical Planning Board 
and thus ensure a condition wherein the viewpoint and needs of the 
motion picture field are at all times clearly stated to the public, the 
professional world, and the government, and are clearly set forth in 
the publications or reports of the Society. 

In conclusion, it is pleasant to pay tribute to the Society of Motion 
Picture Engineers. From its earliest days the Society has been in- 
terested in the video field and, later, in the video-audio field. It 
has made many and basic contributions to that field. The motion 
picture industry is greatly indebted to the Society for having laid 
the firm technical foundation on which that industry has grown to 
great achievement and enthusiastic public acceptance. 

Whatever the Society has done in the past may be regarded as a 
promise of its like accomplishment in the future. Indeed, the Society 
has the encouraging prospect of remaining both a technical leader 
within the motion picture industry, and one of the major assets of 
that industry. It is hoped and anticipated that the Society will 
carry forward with equal success, in the field of theater television, 
the constructive activities which it has carried out in the sister art of 
the motion picture. 

118 GOLDSMITH February 


CHAIRMAN D. E. HYNDMAN: I observe a number of representatives of film 
manufacturers in the audience, who will be 'very much interested in the com- 
mercialization of color television, either small or large, for a purely ulterior motive. 
' MB. W. H. OFFENHAUSER, JR. : To those of us who have seen radio grow, have 
seen sound films grow, and hope to see television grow in whatever form, history 
does repeat itself, and there was one portion of Dr. Goldsmith's talk that speci- 
fically brought this to mind. That was the little section about high-speed pro- 
cessing in the projection room. 

As I remember, we discarded crystals in order to eliminate them and their 
uncertainties, and brought in vacuum tubes. As the art developed, we went 
into what we call plumbing, a little later on, and back to crystals. 

It seems that when we look back over the history of motion pictures, we have 
done something quite similar there. In the very early stages of motion pictures, 
we had no developing machines and, accordingly, the processing laboratory or 
the studio stage was either in the studio or very close to it, merely because the 
number of square feet available in a studio of the early days was very small. 
However, we thought we made a tremendous advance when we took out the 
developing machine. Originally, we operated that by hand, and then we drove 
it with a motor, and we removed it far from the studio, relatively speaking, in 
terms of time. We now come along with a proposal quite like the crystal. We 
are going to put it back into the studio again. 

DR. ALFRED N. GOLDSMITH: Mr. Offenhauser seems to be correct. The fact 
is that the radio field has gone through an extremely interesting cycle of historical 
repetition. Hertz was the earliest worker in the field, and he used microwaves. 
The microwaves were then decided to be useless for practical purposes, and much 
longer waves were used. We have recently gone back to the microwaves, and 
maybe, in a second cycle, we shall find longer waves useful again in new ways! 

The fact is that history does, to some extent, repeat itself, and that one often 
does find new uses for old things. Thus, the high-speed local processing machine, 
of which some clever examples recently have been, devised, has come back into its 
own; it has even been flying around and operating in an airplane. 

MR. JAMES FINN: Do you suggest the feasibility of interpolating television 
clips into motion picture programs as presently constituted? I should think that 
that would take a great deal of chest-puffing on the part of an art that is already 
sorely pressed to revolve a lOVa-hour program schedule daily for network stuff. 

Programming today is one of the major problems in television. The tech- 
nicians have far surpassed them. When the Federal Communications Commis- 
sion issued its order for ten hours daily, there was great consternation. The 
television adherents now come and say, "We will not only put on television pro- 
grams on a network scale for the swollen budgets of Lux, Rinso, and similar con- 
cerns they being the only people with enough money to do the job but we will 
give you supplementary lines to keep the motion picture theater in business." 

This is quite apart from the structural facilities of existing theaters, which you 
as an outstanding engineer will agree offer some pretty severe problems for the 
installation of television equipment. 

DR. GOLDSMITH: I should like to separate the answer to your question into 


two parts. In the first place, I have not heard that the existing television broad- 
casters have any intention of providing programs for theaters. That is, when I 
spoke of transmitting programs to a theater, I meant transmission by the owners 
of the theater or by a special theater group. If the XYZ theater, for example, in 
Chicago wanted theater television, it would get it in all likelihood from central 
studios and central transmitters owned by the XYZ company, and not, as a con- 
trary procedure, from television broadcasting Station WPQR. Only in the 
rarest instances if, for example, the President of the United States were speaking 
or some tragic disaster had just occurred, might the theaters pick up a broadcast 
program and show it in the theaters. 

So that, as the second point, there would be no systematic correlation or inter- 
connection so far as presently can be seen between television broadcasting, which 
goes to the homes of all, and theater television, which is a form of "narrowcasting", 
and is sent only to a specific group of theaters within the control of the corre- 
sponding company that owns the studio and transmitters. 

MR. FINN: If it should be a delayed program by so much as an hour, then it is 
simply a delayed newsreel. What will be the difference whether we put it on 
film? Moreover^ with feature pictures today running anywhere from 75 to 120 
minutes, it is going to take close scheduling. 

I am talking now about the interpolation of spot tele-events into the motion 
picture program as presently constituted. That is one. 

Second, suppose that we do expand and assert ourselves and we make use of 
this new art. What is going to happen during a period of transition? Shall we 
break into the feature? What would the tele-industry have to offer to us in the 
nature of a feature attraction that we today cannot obtain better from film? 

DR. GOLDSMITH: It is not thought that news events would necessarily come to 
the theaters with any delay. If an event were happening, let us say, in Wash- 
ington or Detroit, it would be picked up by the television cameras, nationally 
syndicated, and sent to all theaters desiring to use it. So that there would be no 
delay so far as we now know. If the event in question happened to be, let us say, 
something like the Kentucky Derby, naturally, it would be scheduled at the time 
the Kentucky Derby took place. 

So that, to answer your first question, I do not see any delay necessarily in- 
volved in theater presentation of news events, provided one knows when the news 
^event is going to happen. When something happens that is unforeseen, the 
theaters may not be able to use it immediately, because they are momentarily in 
the midst of the presentation of something else. That is entirely conceivable. 
However, the news event may be 'so serious and important that they will never- 
theless stop their regular performance and show it. Let us assume, for example, 
that some major disaster occurred in some great city of the United States, either 
by accident or by the design of others. If that disaster occurred, I believe there 
would be few theater exhibitors in this country that would not stop any usual 
performance to show such an event to the people, for one thing, for national 
reasons of interest. 

The other point mentioned is this: What shall be done' about interruptions to 
75- to 120-minute feature films? How shall the exhibitor break in or interpolate? 
I believe that only the skilled exhibitors and program planners could answer such a 
question, or work out a suitable method. 

120 GOLDSMITH February 

However, it is thought that there is nothing sacred about performances having 
lengths of 75 to 125 minutes. So that it may well be that in the future there will 
be some feature films with intervening shorter films between them, thus offering a 
new type of program. Presumably someone will find the way to work out such 

MR. FINN: If I had a very good television set in my home, why should I 
patronize the Gem Theater on the corner? 

DR. GOLDSMITH: The programs which will be seen on television receivers in the 
home are not the programs the audience will see in the theater. In the home 
there generally will be seen commercially sponsored programs of a certain range 
and type of construction with which the public is slowly becoming familiar. They 
are excellent and appealing programs, but they are not the sort of program which 
will be found in the theater. 

If, for example, a great star and the actor who plays opposite her or him were to 
appear in a "television trailer", as it may be called, preceding a feature film in 
the theaters, and to be seen only in the theaters (because it was transmitted on a 
nonpublic frequency), the home audience would know nothing of it. To see such 
a television-theater program, it is necessary to go to the theater and to pay the 
admission price. And it is entirely right and proper that that should be the case. 

MR. McKEE: We finance little exhibitors who build theaters, 600 seaters. 
Their average business is 1200 to 1500 a week. Sixty per cent of all the theaters 
over the country have less than 500 seats. Of that 60 per cent, one half of them 
have less than 300 seats. There are only about 11 per cent over the country that 
have over 2000 seats. That is the motion picture. 

We are ready now to build theaters. We are starting one out on Long Island 
within ten days. Television has us a little disturbed. A 600-seat house with 
land costs $200,000 today, which is a large sum of money. Our banks are very 
much disturbed about television. So we studied television the last four or five 
years, and what it is going to cost us in the theater. 

Today, 50 cents of every dollar taken in these small theaters goes f9r overhead, 
without the cost of the film. So we started to experiment with television. We 
find that the television machine is going to cost us about $25,000. We find that 
we may have to pay a royalty per seat to the manufacturer of the television. We 
find that we have to pay for the show coming in. We have to pay for the show. 
We have to pay ASCAP. We don't know what Mr. Petrillo is going to ask. 

So, on a 500-seat house, averaging a net of 50 cents, if we charge a dollar and* 
fill that house right to the end, which would bring in $500 to us, and if tried to 
amortize some of the equipment, the show would cost us about $2000 for one 
night. That is the case in which we use a theater and we use television as a side 

We have been talking it over with our architect. If we are going to go into 
television, we are going to reverse the situation. We are going to build a tele- 
vision theater, and we will run film as a side line, because if we follow all that you 
have said tonight, the cost of operating the theater, the cost of changing a 'theater, 
fixing the lights, possibly putting the projection machine back of the screen or 
putting it halfway down the aisle and eliminating some seats, and all the other 
things that have been said, it would be impossible to stay in business. 

If we build a television theater in the cheapest form, it is going to cost $150,000. 


If we try to amortize that all the way through, we shall have to charge about $3 
admission, for a 500- or 600-seat house. We are trying to find out from where we 
are going to get the business. The only thing may be a prize fight at "ten o'clock. 
If we put it in our regular theater, we shall have to change the entire audience 
before that, and then we have to charge double admission for prize fights. 

There is no afternoon business. The average small theater over the country 
in the matinee business does not do $8, or $9, or $10. In some of the big houses 
they do not even do $50. If we are going to have any matinee business, what 
are we going to run in the theater when we use television? We cannot use base- 
ball. Maybe we shall use home economics. We do not know; but if we are 
going to charge a dollar admission in the afternoon for women to come in and see 
how to cook or bake a pie, we are not going to get the money. We cannot even 
get them in there to see a good picture and charge thirty cents in the afternoon, 
for regular theater programs. If we are going to charge them for television and 
have most of the show in film and a little of it is going to be a live show, and 
have the costs coming in, we shall all go broke. 

If you say we are going to have co-operative ideas and coaxial cable and a 
half-dozen things in which a group of exhibitors are going to combine together 
there and show, if you have had any experience with exhibitors you will know 
that it either ends up with just two running the business or it ceases to exist. 

So we can see television only from one viewpoint, and that is a separate tele- 
vision show, and just try to get an RFC or an FHA loan on that. 

DR. GOLDSMITH: Mr. McKee's points seem extremely well taken, and they 
emphasize two things: First, as I have pointed out, the television solution for the 
type of theater he is talking about may be a type of television equipment which 
is not now available, methods not yet discussed, and the like. The solution in 
each case depends largely on the sort of theater, and therefore the solution in each 
case may be different. It may well be that for the small theater, a large television 
program syndication group and more emphasis on television would be required. 

The paper which I presented was addressed primarily to the larger theaters, 
where major and fundamental operations will remain on film, at least for quite a 
time into the future. However, the important point that I wish to stress in con- 
nection with Mr. McKee's remarks is that obviously there has been accomplished 
exactly what was desired; namely, to point out that the exhibitors themselves have 
to tackle this problem and solve it. The engineers cannot give showmen the an- 
swers. If the exhibitors tell the engineers what they want and can afford to pay 
for, and how they want to use it, the engineers will find the answer or tell the ex- 
hibitors that they cannot. They will probably find the answer; they usually have. 

However, the one thing that was particularly desired was to stimulate people 
into thinking out the answers to the showmanship problems. This audience 
certainly is indebted to Mr. McKee for what he has said in that connection, be- 
cause he is clearly thinking his way through the problem; and if others will do 
the same, we may be confident that it is going to be solved. 

New Developments in Mercury 
Lamps for Studio Lighting* 



Summary Development work on mercury lamps in England progressed 
at an accelerated rate during the past eight years in connection with war 
projects. The result of this work has been new types of such lamps in 
which the source shape has been modified, the source brightness increased, 
and the color quality improved so much as to suggest important advantages 
for motion picture and television studio lighting if economic factors permit 
their use. 

In this paper the author summarizes and analyzes data made available to 
him from research laboratories in England. 

THIS is A report and an appraisal of the results of extensive develop- 
ment work in England on mercury sources undertaken first 
for military purposes and subsequently continued with a view to 
motion picture and television studio lighting. The primary objective 
was to overcome the defects of previously available mercury sources. 
Light sources and lighting have always been subjects of major 
importance to the motion picture and television industries. While 
mercury lamps of the forms and characteristics heretofore available 
have not been acceptable for use in the modern motion picture studio, 
certain inherent features of such sources have long been recognized as 
desirable attributes in these lighting fields. These have included: 

1. Relatively high efficiency in conversion of electrical energy 
into light. 

2. Relatively low heat radiation. 

3. Long life. 

4. Silent operation. 

5. Cleanliness. 

Their usefulness in these particular lighting fields has been limited for 
the following reasons : 

1. The shape and dimensions of the source did not lend themselves 
to effective use in appropriate types of lighting equipment. 

* Presented September 30, 1947, at a meeting of the Pacific Coast Section of 

the Society of Motion Picture Engineers in Hollywood. 




2. The starting and operating voltages exceeded the voltages 
generally available in the studios and the lamps were not designed for 
operation on direct current. 

3. The "warm-up" time of a cold lamp and the restarting time of 
a hot lamp were excessive. 

4. The maximum wattage 
was limited to a value, entirely 
too low to serve many of the 
lighting needs of the motion pic- 
ture studio. 

5. The color quality of the 
light produced was not suited 
to color photography and, in 
fact, was not so good as desired 
for black-and-white photog- 

We, in America, are indebted 
to the British lamp manufac- 
turers for the tremendous strides 
which have been made toward 
the solution of these difficulties. 
Development work on such 
sources in England proceeded 
at an accelerated pace during 
the war in connection with proj- 
ects sponsored by the British 
Admiralty while the develop- 
ment facilities of American 
manufacturers were assigned to 
other projects. Data included 
in this paper have been -'sup- 
plied by the British-Thomson- 
Houston Co., Ltd., and more 

particularly by H. K. Bourne, MSc., M.I.E.E., F.R.P.S., of the 
Research Laboratory of that company. 


The new type of mercury lamp, Fig. 1, is conspicuously different in 
appearance from the types previously available. The lamp consists 
of a quartz bulb, approximately spherical in shape, containing near 

Photo Courtesy of British-Thomson-Houston 

Co., Ltd. 

Fig. 1 Developmental 10,000-watt 
"compact-source" mercury lamp and 




its center two relatively massive tungsten electrodes with dome or 
chisel-shaped ends. These electrodes are spaced from a few to per- 
haps 10 millimeters apart. Thus, instead of the familiar long slender 
source characteristics of mercury lamps in general, the new design re- 
sults in a source of light which is approximately spherical in shape. 
The advantages of this form are apparent not only in the types of 
equipment used for motion picture and television studio lighting but 
for projection purposes 1 " 3 as well. 

Such lamps have been made in various ratings between 100 and 
20,000 watts although in some ratings the lamps are still in a 
developmental form. 

A single-ended construction has also been developed, Fig. 2. 

Photo Courtesy of British-Thomson-Houston Co., Ltd. 
Fig. 2 Single-ended construction of "compact-source" lamp. 


It is a well-known fact that high source brightness is a prerequisite 
of virtually all light sources used for studio lighting; only thus can the 
requisite optical control of sufficient amounts of light be achieved. It 
is quite proper, therefore, to examine the British development from 
this standpoint first of all. There are two general methods available 
for obtaining high source brightness. The first of these is exemplified 
by the water-cooled mercury lamp 4 ' 5 of the H-6 type available in this 
country since 1938. This type of lamp, consuming 1000 watts, has a 
source length of approximately 1 inch (2.5 centimeters) and has a 




maximum brightness of 30,000 candle power per square centimeter. 
Destruction of the quartz at the high loading of the small quartz tube 
is prevented by the cooling effect of a stream of water flowing rapidly 
over the surface. The high light output of 65,000 lumens from this 
1000-watt lamp and the small amount of heat radiation are important 
advantages, but as the source is long and very narrow, special optical 

Dperating vertically on D C 

Fig. 3 Brightness distribution in the arc of a 5000-watt 
"compact-source" lamp. 

systems are generally required for efficient light collection. Again, 
for many applications the relatively short life and the necessity for 
using water cooling detracts from the other good features of this source. 
The second method of increasing the brightness of the mercury- 
vapor source has been developed very fully in Great Britain by several 
lamp manufacturers. In such lamps, generally known in England as 
"compact-source" lamps, the high brightness is a result of the reduced 
electrode spacing previously described. At the same time, the quartz 




bulb is designed with a surface area sufficiently great to prevent 
overheating, but small enough to ensure a relatively high operating 
pressure. No forced cooling is required as natural convection cooling 
and surface area limit the temperature of the surface of the bulb. 
The high concentration of energy in the arc column results in maxi- 
mum brightness values of approximately 100,000 candle power per 
square centimeter. Developmental lamps are reported to have given 
values which are higher than those attained in the high-intensity car- 
bon arcs. 6 Fig. 3 shows the brightness distribution for a 5000-watt 
lamp of this type. 


The luminous efficiency of the "compact-source" lamp depends on 
the lamp wattage but is normally between 45 and 55 lumens per watt. 
The light output falls gradually to about 75 per cent of its initial 
value at the end of life, owing to blackening of the bulb. The average 
life of 250-, 500-, and 1000-watt lamps in service is generally about 
500 hours. 


The arc of the "compact-source" lamp will strike immediately when 
a potential of more than 200 volts alternating current or 275 volts 
direct current is applied to the terminals. More important, however, 
it may also be established at lower voltages (115 volts, for example) 
if ionized by either a Tesla coil or a momentary high- voltage impulse. 
Like all arcs, however, the electrodes would be destroyed if this volt- 
age were maintained at the electrodes once the arc is established. 
Therefore, a ballasting impedance (if the supply is alternating current) 
or a ballasting resistance must be used in series with the arc to limit 
the lamp current. Since a resistance ballast must be used on the 
direct-current systems available in motion picture studios the over-all 
power requirements of such operation are indicated in Table I. 



Lamp watts 








Lamp current, amperes 








115-volt direct-current sup- 

ply ballast resistance, 








Total watts 







230-volt direct-current sup- 

ply ballast resistance, 









Total watts 











The "compact-source" mercury lamps are subject to the same 
criticism of slow start and restart time that applies to almost all other 
mercury sources. The time required to reach full output and proper 
color after being first turned on is of the order of 5 to 10 minutes, 
Fig. 4. Similarly if the electrical Supply is interrupted when the lamp 

-C <u 








Time - m!n$. 

, Fig. 4 Warm-up characteristics of a low-wattage mer- 
cury lamp. Higher-wattage types require substantially 
the same warm-up time. 

is operating it will not restart normally for perhaps 5 to 15 minutes, 
after which the warm-up cycle may be repeated. 

In some applications where the lamp is in continuous operation 
these delay times are not important but there are other cases where 
such delays represent a serious disadvantage. For example, in 
motion picture studio illumination it is often difficult to forecast the 




exact number of lamps which will be required as the cameraman often 
calls for additional units to be switched on at short notice, and delays 
of some minutes obviously cannot be tolerated. It has therefore 
been necessary to devise practical methods of avoiding this difficulty. 
There are two ways by which the delay time can be minimized or 
avoided. 7 In the first of these the lamp may be warmed up some time 
before the light will be required. The current in it is then reduced to 
10 to 15 per cent of its full load value and a lagged cover is placed 
around the bulb both to obscure the light and to conserve the heat in 

the lamp, Fig. 5. With this 
cover in place, the "simmering" 
current is sufficient to maintain 
complete vaporization of the 
mercury and full light output 
may be obtained instantane- 
ously by opening the cover and 
simultaneously increasing the 
current to its normal value. 
The life of the lamp is reported 
to be scarcely affected by sim- 
mering as at the low simmering 
wattage apparently no deteriora- 
tion of the lamp takes place. 
The current is reduced to the 
simmering value by inserting 
an additional resistance in series 
wit"h the lamp. This resistor 
may be located inside the sim- 
mering cover so that the addi- 
tional heat dissipation from it 
helps to maintain the tempera- 
ture of the bulb and so improves the over-all efficiency of operation. 
In the second method, the lamp is mounted inside a glass-walled 
oven, Fig. 6, which is maintained by heaters at a temperature suffi- 
cient to vaporize the mercury in the lamp completely. The arc may 
be ignited instantaneously by applying a high-voltage impulse either 
across the main electrodes in the lamp or between an auxiliary elec- 
trode and the adjacent cathode. In the latter case a momentary volt- 
age of around 15 kilo volts is generally sufficient to insure reliable 
reignition of the arc. Without the auxiliary electrode an ionizing 

Photo Courtesy of British-Thomson-Houston 

Co., Ltd. 

Fig. ' 5 Developmental assembly 
of mercury lamp in "simmering 5 ' 
housing to conserve heat for quick 
restart at full output. 




potential of 30 to 50 kilo volts will be necessary. Full light output 
can be obtained whenever it is required and even if the supply is 
interrupted or has been switched off inadvertently, the arc can be 
reignited immediately. 

If desired these two methods may be combined by using the high- 
voltage impulse method of arc reignition with a lamp which has been 

Photo Courtesy of British-Thomson-Houston Co., Ltd. 

Fig. 6 Developmental housing for mercury lamp to pre- 
heat lamp for quick start by ionizing pulse. 

simmering to cater for the condition where a simmering lamp has been 
extinguished and from which light is again required immediately. 
By applying these methods the light from a "compact-source" lamp 
may be obtained virtually instantaneously whenever it is needed. 
The only remaining delay is the initial period of 10 to 15 minutes 
needed for a cold lamp to warm up in the first instance. If all the 
lamps likely to be required are warmed up initially then delay times 
become of no practical importance. 

130 CARLSON February 


When mercury lamps are operated on alternating current the light 
output varies in proportion to the cyclic variations of the current. 4 
Therefore, if such lamps are used for motion picture photography or 
projection, the frequency of the alternating current must be some 
multiple of the frame frequency, or direct current must be employed. 
Since the same problem exists with carbon arcs and since direct cur- 
rent is already available for such sources the latter procedure is the 
more convenient. 


A photographic light source must operate steadily and produce a 
constant light output and these conditions appear to be fulfilled ad- 
mirably by the "compact-source" lamp. Reasonable fluctuations in 
supply voltage produce only comparatively small changes in the 
characteristics of "compact-source" lamps. Such variations have no 
appreciable effect on lamp life or on the color of the radiation while 
the considerable effect of supply-voltage variation on both these 
characteristics in the case of an incandescent filament lamp is only too 
well known. 

The effect of supply-voltage variation on the characteristics of a 
250-watt "compact-source" lamp operating from a 230-volt supply is 
shown in Fig. 7. In the case of a 5-kilowatt mercury-cadmium lamp 
operating from a 115-volt direct-current supply a reduction in supply 
voltage of 1 per cent reduces the light output by 3 per cent. 


In a "compact-source" lamp a stream of hot vapor, generally 
known as the "arc flame", rises above the arc because of the action 
of convection currents in the bulb. When the lamp is operated 
with the arc vertical, this arc flame is dispersed by the upper elec- 
trode and is thereby prevented from playing on the quartz bulb. 
If the lamp is tilted, however, the flame will impinge on the quartz and 
will cause overheating which may lead to premature failure of the 
lamp. This arc flame consists of ionized vapor and may therefore be 
deflected by a magnetic field. It is thus necessary to employ a 
magnetic deflector with "compact-source" lamps to prevent the arc 
flame from playing on the quartz when the lamps are tilted out of the 
vertical position. A mechanism has been developed for studio spot- 




lights which brings the magnetic field into play automatically as soon 
as the lamp is tilted so that operation at any angle may be achieved. 


ry little actual experience is available at this time to permit 
)ritative statements on the subject of safety. However, certain 
general observations are possible and should be mentioned here. 


yu ys 

% Mains voltage 

Fig. 7 Effect of variations in supply voltage on a typical mercury 
lamp on resistance ballast. 

Mercury lamps emit radiations in that portion of the ultraviolet 

spectrum which can cause sunburn or conjunctivitis. These radia- 
tions are absorbed and rendered harmless by the outer bulb which is 
used with most such sources. Since such an outer envelope is not 
used with the mercury lamps described here it follows that they must 
be enclosed in housing providing the same degree of protection that 
prevails for carbon arcs. 




It would also seem that the use of a protective housing serves a 
second important purpose. Very little is known at this time of the 
mechanical strength of the quartz bulb used. We do know, however, 
that the internal pressure of the mercury vapor within the bulb is 
high when the lamp is at normal operating pressure and that, there- 
fore, the hazards of bulb failure must be considered. 


Unlike tungsten-filament lamps or carbon arcs, the light from a 
mercury lamp is emitted at specific wavelengths in the spectrum, and 
these wavelengths are always present whenever mercury is used. 
The unfortunate difficulty with mercury arcs has been that these 
radiations do not occur at the proper wavelengths and in the proper 

Wavelength J 

Fig. 8 Spectral distribution of radiation from a 5000-watt "compact-source" 

mercury lamp. 

relative amounts to produce good color rendering when used to expose 
color film. A serious deficiency in the red region of the spectrum has 
been particularly apparent. 

Some improvement in color quality is achieved by the same two 
methods that produce high source brightness. In such cases, the 
radiation comes from wavelength bands of appreciable width and cea- 
tering at the specific wavelengths characteristic of mercury and, even 
more important, these radiations are supplemented by a lower inten- 
sity radiation with a continuous spectrum, including the red region, 
Fig. 8. This improvement, however, is still insufficient to satisfy the 
requirements of any color film. 

Certain other metallic vapors have been added to mercury to in- 
crease red radiation and to fill in the gap in the mercury spectrum in 




the blue-green region (about 5000 angstroms). The number of 
metals available for this purpose is, however, limited for several rea- 
sons. The most satisfactory results were obtained several years ago, 
both here and abroad, by the introduction of cadmium and/or zinc 
which produce not only a generous amount of red radiation but also 
radiation in the blue-green region. However, at that time the de- 
velopments did not appear promising due to the fact that there was 
some loss in luminous efficiency. 

Recent studies by the British lamp manufacturers now indicate 
that, when cadmium is introduced in the "compact-source" types of 
1000 watts or more, not only is there considerable improvement in 

3000 4000 5000 bOOO 700C 

Wavelength I 

Fig. 9 Spectral distribution of radiation after cadmium has been added to the 
mercury lamp of Fig. 4. 

color but that it is achieved at a loss in efficiency of only about 5 per 
cent. A comparison of Figs. 8 and 9 indicates the important magni- 
tude of the improvement. Tests described later indicate that the 
color quality of the light from high-power mercury-cadmium lamps 
is suitable for use in connection with modern processes of color 
! photography. 


Light sources used for photographic purposes must also be judged 

j in terms of their photographic "speed" and the faithfulness with which 

they and the film can record the visible colors either on a gray scale 

with the proper luminosities or in color. Some such tests have been 




made in England but they are not sufficiently complete to provide a 
basis for a conclusive statement. 

Mercury lamps without cadmium have been used to expose a vari- 
ety of photographic materials ranging from panchromatic film to 
bromide paper, and increases in "speed" relative to an equal amount 
of tungsten-filament illumination were found which ranged from 10 
to 690 per cent, respectively. When compared on the basis of equal 
over-all watts on alternating current, gains in speed ranging from 
more than two times to about 14 times are reported. This agrees 
with our own experience in testing other types of mercury lamps. 

(a) (6) (c) 

Fig. 10 Ilford color charts photographed oh panchromatic film when 
illuminated by (a) tungsten filament lamps, (6) mercury lamps, and (c) mer- 
cury-cadmium lamps. The left-hand side of the charts include colors of the 
spectrum ranging from red at the top to violet at the bottom. The right-hand 
side consists of neutral panels in shades to match the visual luminosity of 
the adjacent color. 

Color rendering also agrees with our own observations. Mercury 
produces excessive exposure on panchromatic film in the blue and 
violet portions of the spectrum and insufficient exposure in the red. 
The reverse condition is, of course, observed with tungsten-filament 
sources. On the other hand, the same type of test using a mercury- 
cadmium "compact-source" lamp shows a much more favorable bal- 
ance of grays in terms of luminosity, Fig. 10. 

Photographs of color charts illuminated with 5-kilowatt mercury- 
cadmium "compact-source" lamps have also been made in Techni- 
color and other color photographic processes and some excellent re- 
sults have been obtained. Practical tests show that there is little 


difference between the color rendering given by these lamps and by 
either the high-intensity carbon arcs or properly filtered tungsten 
now being used to expose Technicolor film. Again with Kodachrome, 
Dufay-color, and Ansco Color, the color reproduction appears to be 
good. These remarks must not, however, be taken to mean that this 
is the official view of the various color-film manufacturers. 


Engineers in the field of motion pictures and television can readily 
point to many applications for sources having the characteristics de- 
scribed. It may be of interest to know something of the uses for 
which these sources have been tried in England. H. K. Bourne 
reports : 

1 'Studio Lighting 

"The first experiments with the studio compact-source lamp were 
made by F. V. Hauser, Messrs. Technicolor, and the writer at Denham 
and Pine wood Studios in 1945, on which occasion photographs of color 
charts were taken in Technicolor using a 5-kilowatt compact-source 
mercury-cadmium lamp in a converted MR. 65 spotlight housing/ 
The comparison with high-intensity carbon-arc illumination was so- 
good that tests on a larger scale were organized. These were made in 
November, 1945, when some small sets were illuminated alternately 
with seven spotlights fitted with these lamps and with a similar num- 
ber of MR. 65 high-intensity arcs. Short films were taken in Techni- 
color under the two forms of illumination and it was difficult to differ- 
entiate between them. The color reproduction was regarded as being 
very satisfactory by the film studio engineers. These experimental 
films were shown at the Illuminating Engineering Society's Convention 
in London in May, 1946, to a large audience among whom they 
aroused considerable interest and surprise. 

"Since that time further tests have been made and the lamps have 
been used with complete success in the black-and-white film produc- 
tion, The Crowthers of Bankdam,' by Archibald Nettlefold Studios.. 
The first experimental unit to be used in a studio was a converted 
MR. 65 spotlight fitted with a 5-kilowatt mercury-cadmium lamp 
illustrated in Fig. 11. In subsequent tests MR.90 housings fitted with 
an oven for maintaining the lamp temperature and an auxiliary circuit 
to provide instantaneous arc reignition were used. (See Fig. 6.) A 
housing in which the lamp is mounted inside a simmering cover which 




opens automatically as the current is raised to its full value is illus- 
trated in Fig. 5. In this photograph the simmering cover is shown in 

Photo Courtesy of British-Thomson-Houston Co., Ltd. 
Fig. 11 Development 5-kilowatt "compact-source" lamp 
in converted fresnel-lens spot. 

the open position. The magnetic deflector is also visible on the side 
of the simmering oven. While experiments made so far have been 
carried out chiefly with spotlights, the lamps are equally well adapted 
for application to 'broads' and units of this type are also being built 


and tested. The lamps have created a most favorable impression 
among the studio engineers who welcome the stability of operation, 
the complete absence of noise and smoke, the lack of attention, and 
the reduced heating effect. A comparatively large number of units 
is shortly to be installed at Pinewood Studios for use in forthcoming 
film productions. 

'The compact-source lamp has also proved to be most effective for 
television studio lighting. These lamps have already been used by 
the British Broadcasting Corporation at Alexandra Palace television 
station where they were first employed for lighting a feature program 
entitled 'Picture Page' in August, 1946. The advantages of the lamp 
for television lighting are the considerable reduction in heating, par- 
ticularly as compared with incandescent filament lamps, an improve- 
ment in picture quality due to absence of "mush" owing to reduced 
infrared radiation, and a spectral-radiation distribution, which, in 
combination with the sensitivity curve of the television camera, gives 
an excellent color rendering in monochrome. 

"Film Printing 

" Another important application of compact-source lamps is in film- 
printing machines. Recently some new fine-grain emulsions with a 
relatively low sensitivity have been introduced and it has been neces- 
sary to reduce the speed of the printing machine to secure an adequate 
exposure. The high brightness of the source and the high actinic 
value of the radiation from the compact-source lamp enable a consider- 
able gain in printing speed to be realized. A disadvantage is that the 
light output cannot be controlled over a wide range by variation of 
lamp current so that these lamps are normally only fitted to machines 
having aperture control. A 250-watt lamp, which has been used very 
successfully in Great Britain for film printing, has enabled printing 
speeds to be maintained or even increased in spite of slower emulsions. 
As in the case of both studio illumination and in film projection, 
direct-current operation is essential in order to avoid the stroboscopic 
effect which would cause variations in exposure if the lamp were oper- 
ated from an alternating-current supply." 


It is difficult to speculate as to the future possibilities of "compact- 
source" lamps, but it seems inevitable that they will play a prominent 
part in the motion picture and television industries in the years to 


come. It would appear that all of the major technical difficulties 
which have restricted the use of mercury-vapor lamps in studios have 
either been overcome or means are now available for doing so. 

Of course this new development brings with it new problems. For 
example, everything at this time indicates a much higher unit cost of 
light source than has been previously considered by the studios. On 
the other hand, the relatively long life which seems possible, the high 
output per source, and the simplicity of operation may still result in 
advantages, economic and otherwise, which will compare favorably 
with other illuminants. 

It is expected that intensive development work now in progress here 
and with which the author is associated, will provide an early oppor- 
tunity for a comprehensive study in American studios. It must be 
understood, however, that the results reported here apply to lamps 
made largely by hand by skilled quartz workers. In order to make 
such lamps economically practicable here, designs adapted at least in 
part to production methods are indicated. It therefore follows that 
such lamps may bear little resemblance to the types illustrated in this 


(1) V. J. Francis and G. H. Wilson, "Air-cooled high-brightness mercury 
vapour lamps and their applications to projection," Trans. I. E. S. (London) 
vol. 4, p. 59; April, 1939. 

(2) H. K. Bourne, "A compact-source projection lamp," /. Sci. Instr., vol. 
22, p. 107; June, 1945. 

(3) E. H. Nelson, "High-intensity mercury- vapour arc lamps," /. Gen. Elec. 
Co., vol. 14, no. 2; August, 1946. 

(4) E. B. Noel and R. E. Farnham, "A water-cooled mercury arc," /. Soc. 
Mot. Pict. Eng., vol. 31, pp. 221-240; September, 1938. 

(5) E. B. Noel, "Development of water-cooled quartz mercury lamp," /. 
Appl. Phys., vol. 2, p. 325; May, 1940. 

(6) H. K. Bourne, "Characteristics of electric discharge lamps for projection," 
/. Brit. Kin. Soc., vol. 4, p. 15; January, 1941. 

(7) H. K. Bourne, "A new discharge projection lamp for studio lighting," 
Brit.-Thom.-Hous. Activities, vol. 19, no. 6; March, 1947. 

Acoustical Factors in the 

Design of Motion Picture Equipment* 



Summary No simple solution for the reduction of mechanical noise of 
motion picture equipment can be expected. Acoustic designing depends on 
fundamental analysis of the phenomena which cause the undesired disturb- 
ance. The psychology of hearing points out the importance of lowering the 
frequencies. The importance of measuring the spectrum of the noise is 
emphasized in order to find a clue to the treatment. A distinction is made 
between sound-energy sources and sound-radiating sources. A discussion 
of these and the coupling between them is made. Reduction of noise comes 
about by means of (1) lessening the force from the energy source, (2) reduc- 
ing coupling, (3) increasing the mechanical impedance, and (4) lowering the 
radiation impedance. Reducing the coupling appears to have the best 
potentialities. A brief discussion is also made of measuring techniques. 


SEVERAL REQUESTS for information on the silencing of motion pic- 
ture equipment have come to the Armour Research Foundation. 
The literature on the subject is very meager. For instance, not a 
single paper on this subject has been presented before the Society of 
Motion Picture Engineers. Very little work has been done at the 
Armour Research Foundation on this particular kind of equipment, 
but the previous experience of this organization in quieting other de- 
vices has led to a general formularization of a method of attacking 
these problems which may be of interest. 

One general conclusion has been obtained from the queries of the 
engineers which are confronted with these problems. The experi- 
menter is generally not at a loss in getting answers once the problem is 
understood; the chief difficulty has been in not knowing what ques- 
tions to ask. The purpose of this paper will be, therefore, to discuss 
the psychological and physical factors of acoustical design with par- 
ticular application to motion picture equipment. It will become 
apparent that acoustical design is not a matter for hasty improviza- 
tion after the complete mechanical layout is finished, nor is there any 

* Presented October 22, 1947, at the SMPE Convention in New York. 





general cure-all which will reduce the noise. Consistent progress can 
best be obtained by fundamental analysis of the phenomena which 
cause the disturbance and by keeping these factors in mind through- 
out the design stage. 


Of importance to the acoustical designer of any device is some 
fundamental knowledge of the psychology of hearing. Fig. 1 shows 
the Fletcher-Munson curves 1 for the loudness contours of the human 


100 1000 


Fig. 1 Loudness contours of the human ear. Sound 
can be reduced in loudness by either lowering the in- 
tensity or the frequency. 

ear. For reference, conversational level is about 70 decibels between 
100 and 5000 cycles per second, and the average noise level of a home 
motion picture projector is about 50 decibels. Notice that the curves 
are crowded at lower frequencies and lower intensities. In this re- 
gion the loudness can be reduced either by lessening the intensity or 
lowering the frequency. 

In addition to the fact that the lower frequencies are less loud is 
the fact that they are less annoying. Data taken at Harvard Uni- 
versity 2 show that the higher frequencies (10,000 cycles per second) 
are more annoying by 10 decibels than the lowest frequencies, the 




curve rising more rapidly above 1000 cycles per second, which empha- 
sizes the importance of lowering the frequency. 

A very important consideration is the effect of the background 
noise in masking the sound of the device. It is necessary to know the 
noise background to be expected in order to know the design goal 
which is desired. Fig. 2 gives the results of measurements by Bell 
Telephone Laboratories of the noise in the average home. 3 The 
average level is 43 decibels, and about the same level exists in the 
average motion picture theater. 4 The noise per cycle is given in 

ZOO 400 


Fig. 2 Bell Telephone curves of the noise in the average home. 
The noise per cycle is given in curve A : curve B is the noise spectrum 
as measured on a meter having 5 per cent bandwidth. Curve C is 
the level of pure tone necessary to be heard against this background 

curve A. Curve B is the noise as it would be received on an instru- 
ment which has a bandwidth of 5 per cent of the center frequency, the 
effective bandwidth of the average sound analyzer. Curve C is the 
level of pure tone necessary to be heard against the background noise 
of the home. The fact that high frequencies are more noticeable 
against the background noise is another reason for eliminating them. 

To summarize: Low-frequency noise sources are less objectionable 
than high frequencies because (1) the sounds are less loud, (2) they 
are less annoying, and (3) they are more likely to be masked by the 
ambient noise. Of interest, therefore, is the noise spectrum of a 
typical home motion picture projector, which is shown in Fig. 3, along 
with comparative spectra of other devices. It will be noticed that 




the over-all output of the projector has a rising frequency character- 
istic with a peak at about 3000 cycles. This type of spectrum is par- 
ticularly undesirable in that it is practically ideal for masking speech 
or music, and is quite noticeable in the quiet passages of reproduced 
sound. Considerable improvement, more than would appear from 
intensity measurements, would be obtained by materially reducing the 
noise radiated above 300 cycles per second. 


In determining the physical factors which influence noise produc- 
tion, a distinction should be made between energy sources and radia- 


I !! 

A - 10 Electric Fan \ 

8 - Motion Plcturo Pro|Ct 

C - Refrlgerotor 

- Adding Machine 



1\ C 

200 400 600 


4000 6000 IOOOC 

Fro* Gnrol Radio Co. Bulletin SO - June, 1937 

Fig. 3 Spectra of some common industrial products. Of special inter- 
est is curve B, the motion picture projector. The high-frequency com- 
ponents in the noise are particularly undesirable. 

tion sources. As an example, consider the production of sound by a 
violin, which has more analogies to a movie projector than would be 
supposed. The sound radiated from the strings of a violin is extremely 
small compared to that radiated from the body of the violin al- 
though the amplitude of the latter is very small compared to the violin 
string. In this case, the action of the bow on the string is the source 
of energy, the string is a secondary source which is coupled finally by 
the string supports to the body of the violin which is the radiating sur- 
face. The resonant internal cavity of the violin is another secondary 
source which is coupled to other parts of the system and to the air 
through the / holes. These openings are also radiating sources. 


In a movie projector the gear noise cannot be radiated very effi- 
ciently from the gear teeth, whose contact provides the energy source. 
The vibration is coupled to other parts of the projector through the 
bearings and other mechanical links. The larger areas provide the 
radiating sources. Air cavities become other secondary sources 
which emit sound through the various openings in the instrument. 
Air-cavity sources are particularly important in the fan and motor 

The elements of the system can be generalized to be somewhat as in 
Fig. 4. Attention should be drawn particularly to the coupling be- 
tween the various elements. 

The problem is how to reduce the amount of sound radiated. It is 
first necessary to discover the actual sound-radiating sources and their 
coupling to the energy sources. For identification of the locality of 
the radiation source, the stethoscope is a very useful instrument. In 


Fig. 4 Elements in an acoustic radiating sys- 
tem. The sound can be reduced in any of the 
elements. Of particular interest in motion pic- 
ture equipment is the coupling. 

a particular projector, the following were found to be the most notice- 
able radiating sources : the gear-lens-housing assembly, the openings 
in the motor housing, the openings in the fan housing, and some parts 
of the over-all housing. Of particular interest is the radiation from 
the table on which the projector sat. This radiation was rather large 
unless felt or soft rubber pads isolated the projector. 

There are just four general methods by which the sound can be re- 
duced : 

1. Lessen the force from the sound-energy source. 

2. Reduce the coupling to secondary sources and finally to the 
radiation source. 

3. Increase the mechanical impedance of the vibrating parts. 

4. Decrease the radiation resistance of the radiating source. 

The mechanical impedance and radiation resistance will be defined 

144 HARDY February 

below. Items 1, 2, and 3 above control the amplitude of the 
radiating source. The efficiency of the coupling to the air is con- 
trolled by 4. It is believed that not all of these factors are consid- 
ered in the usual survey of the problem. For instance, a gear-noise 
problem which cannot be solved at the energy source, where a great 
amount of attention is usually placed, can possibly be alleviated by 
consideration of the other factors. 

It is well to know the relation between some of these quantities. 
The amplitude of an object is given by the expression 


A = 


where F is the force applied, / the frequency, and Z the mechanical 
impedance. In the simplest case, Z is given by 

where R is the mechanical resistance of damping, M the effective mass 
of the vibrating object, and K the effective stiffness. If the first term 
is the largest, the motion is called resistance-controlled. Similarly, 
there are mass-controlled and stiffness controlled vibrations, the 
former being the more usual except for the very lowest frequencies. 
Notice that at one particular frequency / , the mass and stiffness 
terms are equal 

and resonance occurs. At this point, the impedance is a minimum 
and the amplitude a maximum. The fact that there are no sharp 
peaks in the spectrum of the motion picture projector shown indicates 
that the radiation surfaces are either resistance-controlled or that there 
are so many peaks that the individual ones are obscured in the over- 
all response. 

The radiation resistance is the factor that determines how well the 
radiating source is coupled to the air. Obviously, a large surface is 
more efficient than a small one in moving the air. The large amount 
of mathematics necessary to discuss this subject explicitly is not 
needed here. It suffices to say that for approximately round or 
square surfaces, all parts of which are moving in phase, and whose 


dimensions are small compared to a wavelength, * the radiation resis- 
tance is proportional to the square of the area and to the square of the 
frequency. For objects whose surfaces are not so evenly dimen- 
sioned, the radiation increases less abruptly with area and frequency. 
Two separated areas are less efficient than one of the same total area. 
The radiation resistance can also be reduced by removing baffles 
and changing the sound source from a simple one to a dipole source. 
An analogy can be made to a loudspeaker with and without a baffle. 
The output may be increased 20 or more decibels at lower frequencies 
by a baffle. Partial or total enclosure of the radiating source will also 
reduce the radiation, provided that the enclosed cavity does not reso- 
nate and the enclosure does not act as a baffle. 


Whether these physical facts can be applied to the improvement of 
the noise conditions of motion picture projectors will depend a great 
deal on the ingenuity of the engineers who work with the problem. 
The best method of attacking this particular problem appears to be to 
reduce the coupling between energy sources and radiating sources. 
The immediate goal is to reduce the transmission of high-frequency 
energy. Essentially what is needed is a low-pass filter between the 
energy sources and the radiation sources. The situation is very 
analogous to the power supplies in electronic circuits. Direct current 
is desired without alternating ripple. In some parts of the motion 
picture projector continuous motion or motion repeated at very low 
frequency (say 24 times a second) is needed without the high-frequency 
components. If the higher frequencies, particularly those above 200 
cycles, could be rapidly attenuated, the situation would be greatly 

The electrical circuit for a low-pass filter is shown in the upper part 
of Fig. 5. There may be as many sections as desired. The cutoff 
frequency for such a filter is 


If there is unappreciable resistance in the circuit elements, there will 
be no drop in voltage across the filter. 

Similarly, an ideal mechanical filter would be arranged as shown in 
the lower part of Fig. 5. The cutoff frequency for this filter would be 

* Wavelength at 100 cycles, 11 feet; 1000 cycles, 1.1 feet. 


l lK~ 


If there is very small damping in the mechanical elements, there will 
be no appreciable loss of force acrosss the mechanical filter. 

Of course, nothing so ideal as the above can be expected. It has 
only been drawn to illustrate the method of attack. To reduce the 
transmission, or rather to reduce the frequency above which attenua- 
tion is great, the moving parts should be as massive as possible and the 




- c VOLT 



M M 



Fig. 5 Acoustical analogy between an electri- 
cal and a mechanical filter. In order to reduce 
coupling, the mass should be as large as possible 
and the stiffness of bearings, and so forth, as 
low as possible. 

stiffness of the supports as small as possible. The use of rubber vibra- 
tion isolators is an example of the application of this principle in a 
simple one-section filter. In the motion picture projector the cou- 
pling of the gears and motor to the frame should be accomplished with 
a less stiff support. Coupling by means of belts is one way that less 
stiffness can be accomplished. It should be emphasized, however, 
that it is necessary to hold the lens and film rigid with respect to the 
frame and lamp mounting to eliminate low-frequency vibration which 
would cause the projection to "shimmy". 

Addition of mass is usually objected to, but it should be emphasized 
that this need only apply to the small moving parts coupling the 
motion. With additional mass, no additional force should be 




required to obtain the same steady-state motion, but the action 
will begin and stop at a slower rate. 


There are many sources of sound in a motion picture projector and 
each should be isolated and studied separately, beginning with the 
loudest or the one contributing most to the higher-frequency spec- 
trum. This may mean building of separate drive systems for some 
studies. The most versatile way to examine the phenomena is to 
analyze the spectrum of each source ; in fact, this is sometimes the best 

Fig. 6 Measuring setup for determining the noise spectrum of mechanical 
devices. At the left is a sound-level meter which is coupled to a sound an- 
alyzer. The data can be automatically recorded on the level recorder at the 
right, the motor of the recorder providing the drive for the dial of the sound 

way to determine the source itself. Instead of trying to find an 
operation which changes the intensity of the sound, it is often easier to 
find something which changes the frequency. This points out the 
source of difficulty and perhaps even the cure for the trouble. 

Fig. 6 shows an experimental setup for measuring frequency spec- 
tra. On the left is a sound-level meter which is electrically coupled to 
a sound analyzer. Readings can be taken point to point, but a more 
convenient system is to record the data on a level recorder, such as is 
shown at the right. The motor of the level recorder drives the 
analyzer frequency dial. 

The Armour Research Foundation has also found that it is very 

148 HARDY 

useful to make a record of the objectionable sound on a magnetic 
recorder. The instrument is used more or less as an "acoustical note- 
book" on which comparisons can be made of changes over a consider- 
able period of time. It is also convenient for presenting the results 
to executives, supervisors, and customers. 


This survey has been presented only as an introduction to the sub- 
ject of noise in motion picture projectors. An attempt has been 
made to analyze the problem and to discuss both the psychological 
and the physical factors involved. It is important in the present 
apparatus to reduce the energy in the high frequencies. Potentially 
the best system of attack appears to be to reduce the coupling be- 
tween the sound-energy sources and the radiating sources. 

It has been necessary to generalize in many cases because of the 
nature of the discussion. However, it is hoped that enough specific 
information has been supplied to provide a basis for productive 
experimentation . 


Acknowledgment is made to Mr. R. T. Van Niman and Mr. R. E. 
Lewis of the Society for stimulating discussions of the subject. 


(1) Fletcher and Munson, "Loudness, its definition, measurement, and 
calculation," /. Acous. Soc. Amer., vol. 5, p. 82; October, 1933. 

(2) "The relative annoyance produced by various bands of noise," Harvard 
Psycho-Acoustic Laboratory, PB-27306, Office of the Publication Board, Depart- 
ment of Commerce. 

(3) Harvey Fletcher, "Hearing, the determining factor for high-fidelity trans- 
mission," Proc. I.R.E., vol. 30, pp. 266-277; June, 1942. 

(4) W. A. Mueller, "Audience noise as a limitation to the permissible volume 
range of dialog in sound motion pictures," /. Soc. Mot. Pict. Eng., vol. 35, pp. 48- 
54; July, 1940. 


CAPTAIN A. G. D. WEST: Have you developed a device which gives you an 
instantaneous view of a spectrum, a spectrum of music or a spectrum of noise as 
distinct from the point-to-point device which you showed on the screen? 

DR. HOWARD C. HARDY: Every acoustical engineer would like to have such a 
device. Such things have been made in very elaborate form that take up some- 
thing like a space of ten to twenty feet on the side of the laboratory wall. 

The difficulty in acoustics is that you have to cover about eight octaves. De- 
vices in radio, which have been used to sweep a band of frequencies, cover about 
one octave. No device like that has ever been developed that is very satisfactory 
for portable use. 

A Modern Sound- Reinforcement 
System for Theaters* 




Summary Theaters using "live" talent shows usually require a sound- 
reinforcement system to enable patrons to hear as well as to see the entire 
show. This paper describes a system recently installed in the Roxy Theater 
in New York City, which incorporates many unique features to permit satis- 
factory handling of any stage presentation, however complex. Among 
these features are a control console of unusual design, equipped with mixers 
and volume controls of a new type, and a method of effecting stereophonic 


THEATERS, actors, and public entertainment in general have under- 
gone considerable change since the advent of the silent motion 
picture. Prior to that time, theaters, with the exception of concert 
halls, were comparatively small, well damped acoustically, and of such 
shape that the majority of patrons could hear and follow the dialog 
of well-trained actors. The actors themselves, knowing that they had 
to rely on themselves to be heard, devoted much time to the cultiva- 
tion of a good speaking voice. The relationship between actor and 
audience was close and intimate. Concert halls were somewhat 
larger and well suited for musical programs but not for types of enter- 
tainment that relied on the speaking voice. With the coming of the 
motion picture several other types of theaters evolved. One was the 
small auditorium used for motion pictures exclusively; another the 
medium-sized combination picture and vaudeville -theater; the third, 
the large theater, featuring first-run pictures accompanied by a musi- 
cal program and vaudeville. The combination theater, while some- 
what larger than so-called legitimate theaters, was yet not too large 
for use by well-trained actors, while the large theater was. 

In the meanwhile, facilities for magnifying the human voice were 
evolved and made commercially available. However, they were, for 
understandable reasons, not immediately accepted for use in theaters. 

* Presented October 24, 1947, at the SMPE Convention in New York. 



Then in 1926 the motion picture acquired a voice, an entirely new art 
developed, and theater exhibitors became acutely aware of a new and 
potent entertainment medium. Coincidentally, interest was aroused 
in reinforcing sound from live talent. In general, technical develop- 
ments in connection with the production and reproduction of sound 
pictures grew at a rapid pace resulting in a nearly perfect product, 
whereas those concerned with sound reinforcement did not. 


While these developments were in progress, theater programs 
changed. Vaudeville became practically extinct, combination thea- 
ters adopting a straight picture policy. Today only the larger theaters 
feature stage shows, usually built around a so-called name band. 
Stage arrangements are commonly used whereon the orchestra or 
name band is grouped upstage so as to form a general background for 
other stage activity. Such arrangements have eye appeal and con- 
form with modern stage-setting design which caters to the eye rather 
than the ear, but they present acute operating difficulties, detract 
materially from the efficiency of the sound system, and necessitate 
expansion of pickup facilities. The difficulties occur because of un- 
desired pickup of high-volume instruments, such as brasses located up- 
stage, by microphones in use downstage. This detracts from the 
efficiency of the sound system in that the louder orchestra instru- 
ments which do not require reinforcement tend to be overemphasized. 
The additional pickup facilities are required to enable the audience to 
hear pianos and string instruments which, without reinforcement, 
would not be heard in the auditorium from their upstage location. 

It may be stated safely that today a sound-reinforcement system is 
required to so produce a stage show that all patrons may hear as well 
as see the entire show and to maintain intimacy between performers 
and audience. 


Since many patrons are enabled to hear the performers directly as 
well as by reinforced reproduction, it is imperative that the original 
and its reproduction be identical except in intensity. This means 
that the sound-reinforcement system must be of the highest quality, 
capable of faithfully reproducing the original and at the same time 
magnify it as required. 

Ideally, an auditor should not be conscious of the fact that a sound- 


reinforcement system is in use. This ideal is extremely difficult to 
attain for reasons governed by the physical aspects of the auditorium 
and the relationship between microphone and loudspeaker. Good illu- 
sion dictates that sound should appear to come from its source, but 
here the source is a performer who works into a microphone. It is 
obviously not practicable to place a loudspeaker so as to attain per- 
fect illusion in this situation because acoustic coupling between 
microphone and loudspeaker would be maximum and the amount of 
amplification that could be used without acoustic feedback would be 

In any auditorium the efficiency of a sound-reinforcement system is 
maximum when the coupling between microphone and loudspeaker is 
minimum; i. e., more amplification can be used without regenerative 
disturbances and pickup over a greater distance effected when micro- 
phones are located at a distance from and in back of the loudspeaker 
system. Pickup from a reasonable distance is desirable since it per- 
mits performers more freedom of action, keeps system power demands 
at a minimum, prevents overloads at any point in the system, and 
generally results in better quality than can be obtained if the pickup 
distance is restricted. 

For these reasons a modern loudspeaker system usually cannot be 
placed on the stage. It could be suspended from the proscenium arch 
but such mounting, while efficient if low enough, is unsightly and not 
generally used. It is therefore necessary to mount loudspeaker sys- 
tems in front of the proscenium at each side of the stage opening, pref- 
erably as far out into the auditorium as possible and in such manner 
that they may be concealed. Such an arrangement necessitates cross 
flaring of horns to cover the auditorium but permits maximum ampli- 
fication to be used resulting in pickup from a reasonable distance, this 
pickup distance decreasing as the microphone is moved downstage in 
the direction of the audience. 


The Roxy Theater in New York City has an auditorium of more 
than 1,500,000 net cubic feet, being roughly 185 feet wide, 150 feet 
long and 85 feet high, seating approximately 6000. It has a mez- 
zanine and a large balcony. It operates on a policy of showing first- 
run pictures and presenting elaborate "In-Person" stage shows, dur- 
ing which the sound-picture screen and horn system are flown and full 
use is made of a rather large stage. It employs a staff orchestra that 


plays on a movable "band-car" located upstage. An organ is also 
used and while the Roxy is equipped with one of the finest, its cham- 
bers have been sealed in under the stage as a result of a former stage 
enlargement. It is therefore necessary to pick up and reproduce the 
organ music by means of the sound-reinforcement system. The oper- 
ating policy also requires that the projection department be enabled 
on certain occasions to use the sound-reinforcement horn system for 
the reproduction of sound on film. In order to meet the current re- 
quirements of the production department and to anticipate their 
future needs, the sound-reinforcement system described herein, the 
third installed during the twenty-year history of the Roxy, was 
specifically designed not only to meet their present requirements, but 
at the same time to provide them with the very best and most flexible 
system of its kind in existence. To accomplish this it was determined 
that a total of 32 microphone circuits for stage pickup and four for 
organ pickup would adequately meet any likely demand. Accord- 
ingly a 36-circuit system, using high-level mixing, with dual driver 
and power amplifiers, having a combined audio output of 150 watts, 
feeding a separate horn system on each side of the proscenium, was 
decided upon. Such a system would also provide rehearsal facilities 
without disturbing those set up for a current show. It was also 
decided that the system should be entirely self-sufficient, fully pro- 
tected by emergency features, flexible in control, and be provided with 
adequate test facilities to assure optimum performance. 

To provide stereophonic reproduction a manual stereophonic con- 
trol was decided upon, to be used in connection with a special amplifier- 
horn selector switch, which would not only enable selection between 
paralleled and stereophonic operation of main amplifiers to be made, 
but would also serve as an emergency measure in the event of failure 
of one of the dual amplifier channels. Limiting amplifiers for use as 
drivers were also considered but discarded in favor of manual control. 
A block schematic of the installed system is shown in Fig. 1 . 


Forty-two Type A-420, two type A-126, two type A-287-F, and one 
type A-323-A Altec Lansing amplifiers are installed. The A-420 is a 
low-impedance, low-level, high-gain preamplifier, having a normal 
gain of 42 decibels. The A-126 is a low-impedance, high-gain power 
amplifier having a maximum gain of 90 decibels and a power output of 
15 watts. The A-287-F is a 75-watt power amplifier with a gain of 15 




decibels which normally works from an A-126. The A-323-A is a port- 
able high-gain, 15-watt, utility power amplifier. All are flat within 
one decibel from 20 to 20,000 cycles per second. The power ratings 

are based on not more than eight per cent intermodulation or two per 
cent total harmonic distortion. The A-126 is equipped with an 
equalizer section which is so designed that the insertion loss at 1000 
cycles per second is the same for any setting of equalization. These 




equalizers have been adjusted for optimum results in this theater, the 
high-frequency droop starting at 5000 cycles per second. Thirty-six 
of the type A-420 amplifiers are used as preamplifiers, four as booster 
amplifiers, and two as utility spares, one serving as a low-level moni- 
tor. These booster amplifiers feed the A-126 and A-287-F amplifiers 
used as drivers and power amplifiers, respectively, through adequate 
control facilities. The A-323-A is used as a monitor amplifier. 

Fig. 2 

In the interest of an over-all low noise level, the filaments of all but 
spare A-420 amplifiers are operated from direct-current filament- 
supply units, and the plate supply is obtained from regulated direct- 
current plate-supply units, Altec Lansing Types E-18 and P-509, re- 
spectively. Five of each type are installed. Four of each supply ten 
A-420 amplifiers through heavy-duty patch cords and plugs. The 
fifth units of each type serve as spares, but are instantly available for 
use through power-patching cords. The filaments of the spare A-420 


amplifiers are energized by alternating current from two separate 
P-509 units. All preamplifiers and booster amplifiers are arranged so 
that they can be removed readily from the circuit or from their rack 
without disturbing any wiring, wiring to amplifiers being terminated 
in suitable jacks mounted on the rear cover plates of metal raceways 
located on each side of preamplifier racks. Connections to amplifiers 
are through flexible cords and plugs, the cords on the two spare 
amplifiers being long enough to reach any location on their racks. 
Fig. 2 shows the amplifiers and power-supply units. 


The number of circuits and other features decided upon would re- 
sult in a console of unwieldly proportions and difficult to operate if 
controls of conventional design were used. Therefore a special con- 
sole design had to be evolved, which was made possible through the 
co-operation of the Daven Company. Their type 600-T attenuators 
having sliders actuated by a lever operated in an approximate straight 
line were selected for all circuits except stereophonic control and organ 
mixing, since they offered the utmost in close grouping and ease of 
operation of the various controls. The special stereophonic attenua- 
tor is of conventional physical design as are the organ mixing controls ; 
the latter being rack-mounted, since only initial adjustments are re- 
quired. The completed console is semicircular in shape, 5 feet 8 
inches wide at its widest point and 30 inches deep. It contains four 
eight-circuit mixing panels, each with a submaster volume control; a 
console master volume control; a master organ control; and a stereo- 
phonic volume control. In addition it contains a jack panel for 
monitoring each individual microphone circuit; a heavy-duty, five- 
position selector switch, operated in a gear-shift fashion as amplifier 
output-horn input selector ; a monitor horn control switch ; two volume 
indicators ( VU meters) and associated meter multipliers ; and a push- 
button pilot-light assembly for control of a heavy-duty impulse-type 
relay in the horn circuit to enable the projection department to use 
the sound-reinforcement systems horn facilities for sound pictures 
when required. 

The connections made through the amplifier-output horn-input 
selector switch are as follows: In the No. 1 position, amplifier and 
horn systems are connected in parallel. In position No. 2, each 
amplifier system is terminated in a suitable load resistor and the horn 
systems are disconnected. In position No. 3, additional horns are 




connected to amplifier and horn systems, all in parallel. In position 
No. 4, each amplifier system is connected to one horn system. Posi- 
tion No. 5 is neutral and not used. Position No. 4 is the normal opera- 
ting position and since the stereophonic volume control is in the input 
circuits of the system amplifiers, manually controlled stereophonic re- 
production is possible. While position No. 1 may be used for normal 
operation, it serves as an emergency protective measure in case of 
failure of one of the main amplifiers. Position No. 2 is provided for 
system tests. Position No. 3 is intended for organ reproduction only. 

Fig. 3 

All instruments are mounted so that they may be removed readily 
for inspection and service, twist-to-lock-type mounting screws being 
used throughout, and each individual piece of equipment is connected 
to its section's terminal strip by means of flexible cables. The in- 
stalled control console is shown in Fig. 3. 


Console mixing is at 250 ohms with controls arranged in groups of 
eight; T networks are used with outputs connected in parallel and 




series resistors are used to maintain circuit impedance. The sub- 
master volume controls form a four-circuit mixer of similar design and 
feeds the console master volume control. The organ mixer, mounted 

on the rack, is a four-circuit, 500- to 250-ohm version of the same 
arrangement and feeds the organ master volume control which is 
located on the console. The paralleled outputs of these two masters 
feed the stereophonic volume control which has one input and two 


outputs. Each output is connected to a driver and power amplifier 
and the stereophonic volume control varies the voltage to these 
"channels" at a ratio determined by its setting. When centered, a 
three-decibel insertion loss is introduced into each channel and equal 
voltages are fed to both. Varying the control, knob to right or left 
varies the signal level in the two amplifier systems. As used, moving 
the control knob to the right reduces the volume from the horn system 
on that side, and vice versa. The control is in 17 discrete steps of 
attenuation, providing no change in total acoustic power from the two 
horn systems but altering the ratio of power in the two in a realistic 

On the console, all controls are so arranged that those most fre- 
quently used are immediately in front of the operator. All so-called 
stage microphones are controlled from the center sections; orchestra 
and footlight microphones are controlled from left and right sections, 


In order to obtain the very best results from the new system it was 
deemed essential that the control console and associated equipment 
be so located that its operator would react as would one of the audi- 
ence, and that he have sole and complete control of all the facilities at 
his command. Experience has shown that space above balconies or in 
unused side loges were to be avoided. Various locations in the lower 
balcony, in the mezzanine and on the orchestra floor were considered, 
but an oblong space adjacent to the rear cross aisle on the left side of 
the orchestra floor was chosen as being best suited for monitoring 
purposes. The floor in this space has been raised and a partial wall 
erected separating all of the control room, except the space above the 
console from the auditorium proper. While the console actually 
forms a lower part of this separating wall, it has been mounted so as 
to protrude somewhat into the auditorium. The control operator is 
therefore effectively a part of the audience and can accurately deter- 
mine the auditorium sound level. He is 45 feet to the left of the 
center line of the auditorium and 145 feet from the center of the foot- 
lights and, from a seated position, has a full and unobstructed view of 
the entire stage. During nonoperating periods, the space from con- 
sole to ceiling is closed by means of two three-section hinged glass 
panels. All facilities are controlled from this room and all sound- 
reinforcement system equipment except microphones and loud- 
speakers are contained therein. 



Fifty pairs of shielded wires, of which 13 are spares, run in two 
separate conduits, connect the control room with a main junction box 
located under the stage. Thirty-six of these pairs are connected to 
preamplifier inputs and have been wired to 52 microphone receptacles, 
strategically located so as to permit use of relatively short microphone 
cables, thereby facilitating the handling j)f microphones. The wire 
shielding is insulated and in each case carried through from micro- 
phone to amplifier. At the control room end, 36 of these pairs are 
connected through multiple, normal-through jacks to their respective 
preamplifiers. Other normal-through jacks connect the preamplifier 
outputs to their associated volume (mixer) controls on the console. 
By the use of patch cords, which are provided, any microphone can be 
connected to any preamplifier although during normal operation none 
is required. 


Of the 36 preamplifier input circuits, four are for organ pickup 
exclusively and are terminated in the organ chamber. The other 32 
circuits are for general sound-reinforcement pickup; 16 circuits are 
terminated on the stage, eight in the orchestra pit and eight in the 
footlights. In order that the orchestra or portions thereof may be 
picked up whether located on the stage as at present, or in the pit, 
parallels of these circuits are also available at microphone receptacles 
on the stage. Parallels of the footlight circuits are likewise available 
on the stage. It is of course intended that these circuits be picked up 
in either of the two locations but not at both simultaneously. Dust- 
caps are provided for all unused microphone receptacles.. In addition 
to the above facilities, the eight orchestra circuits have been extended 
to a new location tentatively contemplated for the orchestra. These, 
too, will be parallels when connected and placed in service. 

The method of handling the so-called "phantom" microphones 
which are mounted on elevators and remotely controlled to disappear 
into the stage may be of interest. The flexible microphone cables are 
short and wired permanently to outlets under the stage adjacent to 
the microphone raise-lower mechanism. From that point the wiring 
is in conduit to outlet boxes adjacent to the microphones' normal 
amplifier input receptacles on the stage, and the microphone leads are 
terminated in short cables and plugs which protrude from their outlet 
boxes. Normally these plugs are inserted in their amplifier input 


receptacles;, however, by removing these microphone plugs their 
amplifier circuits are available for any other use. While four phan- 
tom microphones are available, only one is regularly used, the others 
serve for special stage arrangements. Through connections, micro- 
phone to amplifier, would have left three circuits idle and unavailable. 



One Altec Lansing horn system is concealed in the grillework in 
front of the proscenium wall on each side of the stage opening. Since 
the proscenium opening is 70 feet wide, the horn systems are roughly 
80 feet apart and of necessity cross-flared. Each system consists of 
two 2 by 5 multicellular high-frequency horns with one type 288 high- 
frequency unit each; two folded-type low-frequency horns with one 
type 515 low-frequency unit each; and one 800-cycle, 180-degree 
dividing network. The low-frequency horns are laid on their sides, 
one on top of the other. One high-frequency horn is mounted below 
and one on top of the low-frequency horns. The center line of 
the horn systems is approximately 20 feet above the orchestra floor. 
Each horn system is separately wired to the control-room console and 
additional conductors are wired to suitable outlets for future use 
with additional organ reinforcing horns. 


While the control operator normally is expected to determine 
quality and auditorium volume from his point of vantage in the 
auditorium, complete monitoring facilities are at his disposal. A 
type A-323-A amplifier is provided for use with a monitor speaker, 
and one of the spare A-420 amplifiers for use with a headset as a low- 
level monitor. The jack strip on the console permits these test ampli- 
fiers to be connected to any one of the 32 volume controls that are 
mounted on the console without disturbing a program that is being 
reinforced. In addition, a key on the console connects a monitor 
speaker across the output of either amplifier system. This key nor- 
mally is open and intended to be used only during such time that the 
equipment is not in use. 

Monitoring facilities for the stage manager and organist are pro- 
vided by means of loudspeakers, for the orchestra leader and pianist 
by means of hearing-aid-type headsets, volume controls, and match- 
ing transformers. These are bridged across one of the horn systems. 
These facilities are necessary since without them, reproduction from 


the sound-reinforcement system cannot be heard on the stage well 
enough to pick out cues. 


A high-grade audio-frequency oscillator, containing a suitable 
attenuator and impedance selector, is wired to a pair of jacks. By 
means of a patch cord the oscillator signal may be fed into any channel 
for test purposes. This feature, together with the special amplifier- 
horn-selector switch on the console, which in the test position places a 
dummy load and a volume indicator across both power amplifiers, 
permits complete tests to be precisely and speedily made on the entire 

In addition, two special metering panels having suitable selector 
switches permit the filament and plate voltages to each group of pre- 
amplifiers, and the plate current of each individual preamplifier to be 


Since on occasions, particularly just prior to closing, exit music is 
reproduced by the projection-room equipment from sound on film 
while the sound-picture horn system is flown, arrangements were pro- 
vided to connect the projection room equipment to the sound-rein- 
forcement systems speakers. This is done by means of a six-pole, 
double-throw, heavy-duty, impulse-type relay, located in the control 
room and controlled from push buttons with appropriate signal lights 
in the projection room and at the console. 


The installed system has fully met all expectations. The quality of 
reproduction is good, the noise level low, and the system has ample 
power. It is flexible and extremely easy to operate. The system is 
entirely complete and all facilities are under the sole and direct control 
of its operator. The location chosen for the control room, console, 
and associated equipment has been found eminently satisfactory and 
probably is the best possible under any condition. While it is not 
anticipated that any one show will require a total of 36 individual 
microphones, the system is believed capable of meeting any current or 
possible future demand of an alert production department. 

An Improved 

Intermediation Measuring System* 





Summary This paper describes a new intermodulation analyzer of im- 
proved design and also a two-signal generator for use with the analyzer. 
The equipment is intended for measuring distortion in audio-frequency sys- 
tems by means of paired signals which may be selected in several combina- 
tions from 40 to 12,000 cycles per second. This equipment has been found 
to be particularly useful in determining optimum processing conditions for 
variable-density recording but is also useful in any field where audio fre- 
quencies are employed. 

THE INTERMODULATION method of measuring nonlinear distortion 
in audio-frequency systems has been in successful use for nearly 
ten years. Numerous papers have been published discussing the 
method together with the relative advantages and disadvantages as 
compared with the better-known harmonic-analyzing technique. 1 " 5 
This paper describes a new intermodulation analyzer having a num- 
ber of refinements and features which make it particularly valuable 
for precise measurement work. Also described is a companion in- 
strument in the form of a signal generator which is used to provide a 
source of paired frequencies by means of which intermodulation can 
be measured. 

Although the intermodulation method has been found useful in 
broadcast, public-address, and allied fields, it has proved of greatest 
value in variable-density sound-film recording. In this field the 
measurements have seemed to correlate more closely with observed 
distortion in speech and music than have measurements by other 

Reliable intermodulation measurements may be made in the pres- 
ence of considerable noise since the latter is excluded by filters to a 
greater degree than is the case with the usual total harmonic- 

* Presented October 24, 1947, at the SMPE Convention in New York. 


measuring methods. The intermodulation method also makes possible 
distortion measurements at the higher frequencies in systems having 
limited bandwidth which is not possible at all with the harmonic 
method. For example, most sound-film recording systems have little 
response above 8000 cycles so that measurements of harmonics for 
fundamental frequencies above 5000 cycles is meaningless. But 
intermodulation tests with the combination 100 and 7000 cycles will 
readily show up the type of high-frequency distortion which may have 
serious effects on sound quality. A further advantage of the inter- 
modulation system is in the provision of a phase detector which gives 
a direct indication as to whether the distortion is occurring at the 

Fig. 1 Intermodulation analyzer. 

"toe" or "shoulder" region of the transfer characteristic or both. 
In the case of variable-density sound film the phase detector indi- 
cates whether the compression is occurring in the light or dark region 
of the film-transmission characteristic, when properly calibrated. 


A new intermodulation analyzer unit designed for rack mounting 
is shown in Fig. 1. A cabinet is supplied for the unit where desired. 
The instrument is approximately 19 X 9 X 8 inches in size and weighs 
32 pounds. 

The operation of the RA-1257 Intermodulation Analyzer is based 
on the theoretical considerations presented in an earlier paper, 1 and 
may be summarized as follows, using the block diagram, Fig. 2, as a 


reference. An input signal (from the device under test) consisting of 
mixed high and low frequency is applied to the input of the analyzer. 
The low frequency is between 40 and 150 cycles per second; the high 
frequency is 2000 cycles per second or between 7000 and 12,000 cycles 
per second. The amplitude ratio of low frequency to high frequency 
is generally 4: 1 (i.e., low frequency 12 decibels greater than high fre- 
quency) although this ratio is not mandatory. The effect of changing 
this amplitude ratio is to vary the relationships between distortion 
measured by the intermodulation method and distortion measured by 
any other method. For example, with 12 decibels difference between 
high- and low-frequency amplitudes, distortion measured by the in- 
termodulation method is approximately four times that which would 
be measured by harmonic analysis although the ratio will vary with 
the nature of the distortion; if the difference in amplitude is reduced 
to 6 decibels distortion measured by the intermodulation method 
will be approximately 2.7 times that measured by harmonic analysis. 

Distortion in the input signal consists of amplitude modulation of 
the high-frequency component at the low-frequency rate (or multiple 
thereof); i.e., the amplitude of the high-frequency component will 
vary as the low-frequency component makes one complete cycle if the 
transfer characteristic over which the low frequency swings is non- 
linear. This variation is not necessarily sinusoidal in nature but may 
have any wave shape depending on the transfer characteristic of the 
device under test. The percentage of intermodulation as used here is 
.defined as the per cent amplitude modulation of the high-frequency 
signal. No standard definitions of terms used in this field have yet 
been formulated by authorized groups. 

After being amplified the input is passed through a filter to elimi- 
nate the low-frequency component. Either of two filters may be se- 
lected; for a 2000-cycle-per-second high-frequency signal, a 1500- to- 
2500-cycle-per-second band-pass filter is used; for high-frequency 
signals between 7000 and 12,000 cycles per second, a 6500-cycle-per- 
second high-pass filter is used. The resulting high-frequency com- 
ponent is then amplified and rectified. 

The output of the rectifier is a series of half sine-wave pulses of the 
high frequency with a low-frequency envelope. This envelope is a 
replica of the intermodulation in the input signal. The average out- 
put of the rectifier is adjusted in operation to a reference value of 4 
volts by the use of an input attenuator. The voltage of the low-fre- 
quency envelope is measured by amplifying, rectifying, and applying 







'. M 

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! ^ - > 

Lo W^t '^ #- 



' " vr^r 






it to a vacuum-tube voltmeter. The time constant of this voltmeter 
(0.1 second) is such that its response is intermediate between the peak 
and root-mean-square values of the applied signal. Since the average 
value of the rectifier output will be adjusted to the same value for all 
measurements, the vacuum-tube voltmeter can be calibrated directly 
in per cent intermodulation. 

A distortion phase detector is provided on the RA-1257 Intermod- 
ulation Analyzer for measuring the relative phase of the distortion 
existing in the input signal. This meter indicates whether the high- 
frequency amplitude concurrent with the positive peak of the low-fre- 
quency signal is greater or less than the high-frequency amplitude con- 
current with the negative peak of the low-frequency signal. Ex- 
pressed in simpler terms, it indicates whether compression is occurring 
on the positive or negative half of the low-frequency signal. De- 
flection of the distortion phase meter to the right indicates that com- 
pression is occurring on the positive half; deflection to the left indi- 
cates compression on the negative half. Referring to the block dia- 
gram, a phase detector receives a portion of the input signal from the 
first amplifier on one arm of a bridge circuit and on a second arm of the 
bridge is impressed a voltage of unknown phase from the output of the 
amplifier following the low-pass filter. The output of the phase de- 
tector has a polarity dependent upon the phase of the voltage out of 
the low-pass filter relative to the low-frequency input signal. The 
actual deflection of the phase-detector meter is related to the per cent 
intermodulation but ordinarily only the direction of the deflection is 
noted. If the distortion is all on one end of the transfer characteris- 
tic, the deflection will be proportional to the amount of intermodu- 
lation, but in either direction. If the distortion is equally on both 
ends of the transfer characteristic, there will be no deflection of the 
phase meter. A large per cent intermodulation reading accompanied 
by a small phase-meter reading therefore indicates that the distortion 
is nearly symmetrical with unbalance to the side indicated by the 
phase meter. 


The various circuits and features included in this unit are described 
with reference to Figs. 2 and 3. Provision is made for terminating 
the input either in 600 ohms or in an impedance of approximately 1 

The input control consists of a continuously variable potentiometer 





PI, with 26 decibels of range and three fixed values of attenuation of 
0, 20, and 40 decibels as selected by a switch on the front panel labeled 


The initial amplifier consists of three triode stages, the two halves 
of 7i, a 2C51/396A and one half of 7 2 , also a 2C51/396A with a large 
amount of feedback. The plate load of the third stage is a filter which 
may be either a 1500- to 2500-cycle band-pass filter or a 6500-cycle 
high-pass filter as selected by the FILTER-SELECTOR switch on the front 

The amplifier following the high-frequency filter consists of two 
halves of V 3 , a 2C51/396A dual triode. The output of this amplifier 
is a high-frequency signal, amplitude-modulated at a low-frequency 
rate. The amount of modulation is dependent on the amount of in- 
termodulation contained in the input signal. 

The output of the high-frequency amplifier is rectified by the 6AL5 
double-diode F 4 and the high-frequency component rejected by the 
following low-pass filter which has an attenuation of more than 60 deci- 
bels for all frequencies above 1500 cycles. The terminating resistor 
for this filter is R^. There will be developed across this resistor a 
positive direct voltage with a low-frequency voltage superimposed on 
it. The amplitude of the low-frequency voltage at this point is de- 
pendent on the amount of intermodulation in the input signal. The 
average value of the current flowing through R<& is a measure of the 
amplitude of the high-frequency input signal and is indicated on the 
input meter MI, with the FILTER-SELECTOR switch D s in either the 
2000- or 7000-cycle position. In operation the input attenuator is 
adjusted to give a voltage of approximately 4.0 volts direct current 
out of the low-pass filter when the input meter reads 100 per cent. 

The direct-current component existing at the output of the low-pass 
filter is blocked by capacitor C 7 , and the low-frequency component 
impressed on the primary of transformer T z . The secondary of T* is 
connected to a variable attenuator Z> 4 , which provides for full-scale 
sensitivities on the per cent intermodulation meter of 5 per cent, 15 per 
cent, 50 per cent, 100 per cent, and OFF. 

The output of the attenuator is fed into an amplifier (one section 
of F 5 , a 2C51/396A dual triode) whose voltage gain is adjustable by 
means of variable cathode feedback used as a calibration adjustment. 

The output of the low-frequency amplifier is rectified by the 6AL5 
double diode Fe, used as a full-wave rectifier. The diode load consists 
of -R 33 and C 9 , which combination has a time constant of 0.1 second. 


The polarity of voltage developed is such as to make the grid of the 
following tube negative with respect to ground. 

The voltage developed across #33 is applied to the grid of a triode 
(one half of F 5 , a 2C51/396A) which is used as a vacuum-tube volt- 
meter, in connection with meter M 2 ,which is a high-speed response 
meter with zero current at the right extreme of movement. It is cali- 
brated directly in per cent intermodulation with two scales, 0-5 and 
0-15. With no input to the vacuum-tube voltmeter, but with plate 
voltage applied, the cathode voltage of V$ B and the value of R& are 
adjusted so that M 2 will read per cent intermodulation. The cath- 
ode voltage of VSB is adjusted by the ZERO-ADJUST control P 3 , on the 
front panel ; this control applies a small amount of positive direct volt- 
age to the grid, thus increasing the plate current and cathode voltage. 
In order to accommodate possible extremes of vacuum-tube charac- 
teristics the meter-sensitivity control R& is also included. As noted 
in the previous paragraph the polarity of the direct voltage developed 
by F 4 is such as to make the F 5B grid more negative as the amount of 
intermodulation increases. The plate current and cathode voltage of 
VZB therefore decrease as intermodulation increases, causing the 
pointer of M 2 to move to the right. This type of indication i.e., in- 
creased signal level operating in the direction of vacuum-tube cutoff, 
has the advantage that it is impossible to damage the indicating meter 
due to high values of input. 

The phase detector, consisting of a 2C51/396A dual triode Vi and 
associated circuits, compares the phase relationship existing between 
the intermodulation envelope at the output of the low-pass filter and 
the low-frequency signal at the input to the analyzer. The operation 
of this comparison circuit is as follows : Both halves of Vi are biased 
to cutoff by applying a positive voltage (obtained from the voltage 
divider R^ and R&) to their cathodes which are paralleled. Also 
applied to the cathodes is an amplified sample of the analyzer input 
voltage obtained from the plate of VZ A and further amplified by VZB- 
This causes a series of half sine-wave pulses to flow through each half 
of VT, which in turn results in a decrease in the average plate voltage 
of both halves of Vi. 

The two grids of Vi are excited with voltages 180 degrees out of 
phase with each other obtained from the secondary of 7 1 4 through the 
voltage dividers R^, R^ and _R 46 , #53. Application of these two volt- 
ages will cause the average plate voltage of one half of Vi to increase 
and the average plate voltage of the other half of Vi to decrease. The 


difference between the two plate voltages will be a function of the prod- 
uct of the amplitude of the voltage from T 4 and its phase difference 
with respect to the input voltage. This phase difference will in most 
cases be either or 180 degrees, corresponding to compression on 
either the positive or negative half of the input signal. 

The difference in voltage between the two plates of Vi is measured 
by the zero-center meter M$. Calibration of M 3 is in arbitrary units 
with 100 divisions in either direction from center. Deflection to the 
right is labeled LIGHT and deflection to the left is labeled DARK. It is 
assumed that in operation the input signal will be poled so that com- 
pression on the light end of the film characteristic will cause deflection 
to the left and compression on the dark end of the film characteristic 

Fig. 4 Intermodulation signa ] generator. 

will cause deflection to the right. As a matter of absolute reference, 
compression on the positive half of the low-frequency input causes 
deflection to the right, compression on the negative half of the low- 
frequency input causes deflection to the left. 

A conventional power supply is used with gas-tube regulators so 
that the only external supply required is 115 volts, 50 or 60 cycles 
alternating current. 


Fig. 4 shows the appearance of a new signal-generator unit to work 
with the intermodulation analyzer previously described. This unit 
is normally supplied for rack mounting but may also be furnished in a 
cabinet. It is approximately 19 X 7 X 8 inches in size and weighs 
about 30 pounds. 


The function of the R A- 1258 Intermodulation Signal Generator is 
to add two frequencies without appreciable amplitude modulation of 
one frequency by the other. This summed voltage is then passed 
through any device which is to be tested and the amount of intermod- 
ulation in the output from the device under test is measured by the 
RA-1257 Intermodulation Analyzer or similar device. 

In the RA-1258 unit the two frequencies are generated and separ- 
ately amplified to the desired level. The two frequencies are then 
combined in a hybrid coil after the high frequency has been attenu- 
ated by the required amplitude ratio between the two frequencies. A 
range of output levels between +23 and 44 decibels maximum is 
obtainable, at 600 ohms output impedance. This range of output is 
sufficient for testing most studio equipment without the use of ad- 
ditional amplification. 

The two frequencies may be designated as the low-frequency and 
high-frequency signals. The low frequencies provided by this unit are 
40, 60, 100, and 150 cycles per second; the high frequencies are 1000, 
2000, 7000, and 12,000 cycles. In addition, provision is made for con- 
necting an external signal source to either signal channel in order that 
any frequency combination may be realized. General operating prac- 
tice has been for the ratio of low-frequency amplitude to high-fre- 
quency amplitude to be 4 : 1 . However, in order to permit the possi- 
bility of 'changing this ratio, four fixed ratios are built in, selected by 
means of a front-panel switch. These are 1:1, 2:1, 4:1, and 10:1, 
the last for use in calibration tests. 

In addition to the above combinations of frequencies for use in in- 
termodulation-distortion measurements, an output signal is provided 
for use in calibrating the RA-1257 Intermodulation Analyzer. This 
is a signal of 2000 cycles combined with a signal of 1900 cycles, the 
amplitude ratio between the two being 10: 1. This results in a volt- 
age wave containing 10 per cent amplitude modulation and as such 
can be used for calibration purposes. 

Setup adjustments of the two oscillators are made as follows: Each 
of the two oscillators is set to the frequency desired. The ratio switch 
is set to the amplitude ratio required. Then the signal-selector switch 
is set to the low-frequency position. The low-frequency-signal am- 
plitude control is then adjusted to produce a convenient reading on 
the VOLUME INDICATOR, say midscale. The signal-selector switch is 
then turned to the high-frequency position and the similar adjustment 
made, setting to the same volume-indicator reading as before, which 




automatically will give the amplitude ratio previously set up. The 
signal-selector switch may then be turned to the most clockwise po- 
sition which mixes the two signals and connects them to the output 


The operation of the signal generator will be made clear by refer- 
ence to Figs. 5 and 6. Two separate oscillators each consisting of a 
2C51/396A dual triode (Vi and F 5 ) are used in a resistance-capaci- 
tanced-tuned oscillator circuit. Negative feedback for each oscilla- 

Fig. 5 Block diagram of inter-modulation signal 

tor is provided by the voltage divider R& or R&, and the thermistor 
(Rvi or R V z) operating on one cathode of Vi or F 5 . The action of the 
thermistor is to stabilize the oscillator output against variations which 
would result from changes in gain. The output of each oscillator is 
impressed on a three-stage amplifier, the final stage being push-pull 
for both cases. 

The outputs of the high-frequency amplifier and the low-frequency 
amplifier are combined in the hybrid coil TV The high-frequency 
output of T 2 is attenuated by the bridged-T attenuators connected 
between T 2 and T 3 by the switches D^ and D 3 ; attenuations of 0, 6, 12, 
and 20 decibels are provided in the four positions of DI. The use of 
the hybrid coil for combining the two frequencies results in 
a minimum of intermodulation between the two frequencies by 


isolating the two amplifiers from each other. For most combinations 
of frequencies and at low outputs the intermodulation is less than 
0.2 per cent. 

The output of the hybrid coil T 3 is connected through two attenu- 
ators to the output terminals or to an internal terminating resistor 
#si, the selection being made by the OUTPUT-SELECTOR switch D 3 . 
The two attenuators are capable of continuous adjustment from to 
40 decibels. An output meter is connected directly across the output 
of T 3 . The output from the unit is thus the value read on the output 
meter less the sum of the attenuations shown on the two attenuators, 
providing 600 ohms is connected across the output terminals. 

The output selector switch Z> 3 is provided for the purpose of ad- 
justing the outputs of the two amplifiers independently of each other 
and providing either internal or external termination for the com- 
bined frequencies. In the first position, the low frequency alone is 
applied to the output; in the second position the high frequency 
only ; in the third position both are applied but the output is delivered 
to the internal terminating resistor, and no power is applied to the 
output terminals; in the fourth position the internal resistor is discon- 
nected and the signal is applied to the output terminals. This selec- 
tion is made by the switch section D SA) which grounds the high- 
frequency oscillator output in the first position and the low-frequency 
oscillator output in the second position. 

The unit has its own power supply requiring the use of 115 volts, 
50- or 60-cycle alternating-current input. 

The usual procedure in making intermodulation measurements is to 
send paired frequencies adjusted to a predetermined amplitude ratio 
into the device undergoing test. For example, the usual test will em- 
ploy 100 cycles added to 2000 cycles and having a 100-cycle amplitude 
12 decibels higher than that of the 2000-cycle signal. The output of 
the device, suitably amplified if necessary, is then connected to the 
RA-1257 Intermodulation Analyzer from which the per cent inter- 
modulation can be read. Usually, readings are taken for a range of 
output levels near the region wherein overload occurs. In the case of 
film recording, where several factors generally affect the final result, 
families of curves are frequently plotted so that the optimum con- 
ditions can be more readily determined. 

The intermodulation measuring equipment described is highly sen- 
sitive, yet stable and reliable as well as easily portable. It should be 
a useful tool in many fields of audio-frequency measurement. 



/ . 









O / O-i 











(1) J. G. Frayne and R. R. Scoville, "Analysis and measurement of distortion 
of variable-density recording," J. Soc. Mot. Pict. Eng., vol. 31, pp. 648-672; 
June, 1939. 

(2) J. K. Milliard, "Distortion test by the intermodulation method," Proc. 
I. R. E., vol. 29, pp. 614-620; December 1941. 

(3) J. K. Milliard, "Intermodulation testing," Electronics, vol. 19, pp. 123- 
127; July, 1946. 

(4) Norman C. Pickering, "Measuring audio intermodulation," Elec. Ind., 
vol. 5, pp. 56-58; June, 1946. 

(5). H. E. Roys, "Intermodulation distortion analysis as applied to disk re- 
cording and reproducing equipment," Proc. I. R. E., vol. 35, pp. 1149-1152; 
October, 1947. 

Elimination of the Fire Hazard 
of Projectors Using Nitrate Film* 



Summary An automatic safety sprocket is described, together with 
adapters to fit all types of 35-mm projectors. The conditions which cause 
the safety sprocket to operate to prevent a fire are discussed as well as a de- 
tailed analysis of how fires can be prevented in projectors. 

AFIRE within a projector is caused either by mechanical or film 
failure. Any device which is to protect nitrate film from com- 
bustion must respond automatically when either of these failures 
occurs. A speed-sensitive device which is actuated by the film will 
respond to any mechanical failure. It will also respond to any film 
failure. Such a device is the automatic safety sprocket, which is a 
standard 16-tooth feed sprocket, with a built-in speed-sensitive 
mechanism, rotated by the film as it passes through the projector. 
Because it is driven by the film and is speed-sensitive, anything that 
can happen to the projector or film affects it. Fig. 1 shows the auto- 
matic safety sprocket mounted in a Model K Motiograph. The 
drag of the sprocket on the film is negligible, tension in the film, 
created by the loop, is sufficient to hold the film against sprocket and 
cause it to rotate. 
* Presented April 21, 1947, at the SMPE Convention in Chicago. 





In igniting nitrate film, time and temperature are equal factors. 
The longer film is exposed to a certain temperature, the more likely 
the film is to ignite. A particular sample of nitrate film withstood 
150 degrees centigrade (302 degrees Fahrenheit) for 330 seconds, and 
withstood 180 degrees centigrade (356 degrees Fahrenheit) for 45 
seconds, so there is a definite time lapse after heat is applied to nitrate 
film before combustion. In an investigation of the temperatures at 
the picture aperture, no temperatures were found that did not pro- 

Fig. 1 

vide a time lapse. By taking advantage of this time lapse and apply- 
ing a device such as the automatic safety sprocket to the projector, 
accidental projector fires can be eliminated. The mechanism within 
the safety sprocket acts within l / m of a second after its response to 
any failure The speed with which this sprocket responds to a 
failure depends on the type of failure. For example: The response 
to the loss of the lower loop is Vw of a second, whereas the maximum 
time that can elapse before response to any kind of failure is 5 /i2 of a 
second. This occurs in the event of the parting of a splice or the 
tearing of the film just below the picture aperture. These times 




apply to the safety sprockets being installed in the projector as an 
accessory. However, should the safety sprocket be incorporated in 
the design of the projector, the maximum time can be reduced to 
3 / 12 of a second. 

The speed-sensitive mechanism within the sprocket actuates a 
standard microswitch, normally closed and connected to the closing 
coil of a dowser. Any electrically operated dowser can be used, but 
for economical reasons use of the change-over dowser is most practical. 

Fig. 2 

How soon the automatic safety sprocket reacts to a film failure 
that can cause a fire, depends on how close the safety sprocket is 
located to the picture aperture in the projector. To insure correct 
location the sprocket is provided on an adapter bracket for each type 
of projector. Installation is easy and simple. In placing the safety 
sprocket as close to the picture aperture as possible, it is only neces- 
sary to allow three frames of film between the intermittent sprocket 
and the safety sprocket to stabilize the film as it passes over the 
safety sprocket. Mounted in this position the lower loop is formed to 
ride on the safety sprocket and rotate it at 360 revolutions per minute. 

176 MANNON February 

The speed-sensitive mechanism can be set to act at any predeter- 
mined speed. In practice, satisfactory results are obtained by setting 
it to operate at a ten per cent drop in speed. 

Many projector fires have been caused by the failure of the dowsers 
between the film and light source to be in closed position when the 
light is on. By making the circuit for the lamp the controlling circuit 
this is eliminated. Closing the swtich for the lamp excites the closing 
coil and closes the dowser, should it be open, holding it closed until the 
projector is running in a safe and normal manner. Likewise, the 
danger of prematurely opening the dowser is prevented. When the 
lamp is not lit, the safety sprocket has no effect on the projector, run- 
downs, and tests, and there will be no interference with the open- 
ing and the closing of the dowser. A further safety feature of the 
safety sprocket is control of the projector motor. This provides 
protection from greater damage to the film in the event of a film fail- 
ure, and further damage to the projector should a bearing freeze up. 

Fig. 2 shows the results of failure of the intermittent to move the 
film down the aperture plate. The size of the lower loop has de- 
creased, the film has left the automatic safety sprocket, causing the 
mechanism within the sprocket to operate and close the dowser. 
Traveling at 90 feet per minute, the film left the sprocket approxi- 
mately three frames or 3 /24 of a second after the intermittent failed 
to move the film. 

The foregoing is a new approach to motion picture projection and 
achieves the elimination of accidental projector fires. 

63rd Semiannual Convention 

Santa Monica, California May 17-21, 1947 

Santa Monica Ambassador Hotel Del Mar Beach Club 


The Convention will open on Monday, May 17, with the Annual Business Ses' 
sion at 11:00 a.m., followed by the Get'Together Luncheon at the Del Mar Beach 

The program is shaping up nicely and the Papers Committee urges authors to sub' 
mit Authors Forms and Abstracts to Mr. N. L. Simmons as soon as possible, and in 
any event not later than April 15th. Forms may be obtained from 
E. S. Seeley R. T. Van Niman N. L. Simmons 

250 W. 57 St. 4431 W. Lake St. 6706 Santa Monica Blvd. 

New York 19, N. Y. Chicago 24, 111. Hollywood 38, Calif. 

H. L. Walker 

P. O. Drawer 279 
Montreal, Que., Canada 

There will be nine Technical Sessions with papers on related subjects scheduled for 
presentation as a group. Color will be a topic of major interest, because a number of 
such papers have already been scheduled for sessions late in the week. One of these 
sessions is to be sponsored by the Inter'Society Color Council, and if present plans 
materialize will be followed by an open forum on the general subject of color in a 
variety of applications. 


Requests for accommodations at either the Santa Monica Ambassador Hotel or 
the Del Mar Beach Club should be sent to Watson Jones, Chairman of the Housing 
Committee at The Radio Corporation of America, 1016 N. Sycamore Ave., Holly' 
wood 38, California. W. C. Kunzmann, Convention Vice'President, points out that 
Santa Monica is twenty miles from Los Angeles and ten miles from Hollywood, so 
that members who do not expect to have their cars available should plan to stay at 
Santa Monica. Single rooms will be $5.00 to $6.00; double rooms $7.00 to $9.00; 
parlor suites at $17.50. The Hotel Miramar in Santa Monica, about five blocks 
from the Convention, will have rooms or bungalows available. 


The 63rd Semiannual Dinner Dance is scheduled for 8:30 p.m. on Wednesday, May 
19, in the Magnolia Room of the Ambassador Hotel and will be preceded by a Cock' 
tail Hour in the Rouge Room. 


The Ladies Committee is planning an interesting entertainment program for those 
ladies who attend. 


During the Convention, three theater circuits, Fox West Coast, Hollywood 
Pantanges, Paramount, and Warners, will extend courtesy passes to all registered 
members and their guests, for seven theaters in Hollywood and Santa Monica. 


In addition to special entertainment provided for the Convention, the Santa 
ica area offers ocean fishing, bathing, golf, tennis, and horseback riding. 

Society Announcements 
New Society Officers 

Society Officers, Governors, and Section Officers who were elected in 1947 and 
took office officially on January 1, 1948, were listed in the January issue of the 
JOURNAL. So that new members may know who and where they are and thus 
become better acquainted, I am introducing them here. 

LOREN L. RYDER, President 


John A. Maurer was re-elected for another two-year term, having served as 
Engineering Vice-President since January 1, 1945. He was appointed to that 
office by the Board of Governors to fill the vacancy created when D. E. Hyndman 
was elevated to the Presidency. He was then formally elected in 1946 and has 
continued as one of the Society's most enthusiastic members, guiding our engi- 
neering activities with a calm, steady hand. The work for which he is primarily 
responsible expanded during the war and after to such an extent that the Board of 
Governors in January, 1946, employed a full-time, paid Engineering Secretary on 
recommendation of the President and Engineering Vice-President to handle engi- 
neering correspondence and help administer engineering committee projects. The 
continuity of thought and administration provided by Mr. Maurer's re-election 
will prove to be a valuable asset to the industry and Society membership. Mr. 
Maurer was awarded the 1947 Samuel L. Warner Memorial Award for his many 
valuable contributions to the professionalization of 16-mm motion pictures. 
He is President of J. A. Maurer, Inc., and can be reached at 37-01 31st Street, 
Long Island City, New York. 


James Frank, Jr., newly elected Financial Vice-President, has served on Society 
committees and the Board of Governors continuously since 1937, when he became 
Secretary of the Society. In 1947 he planned and supervised the Theater Engi- 
neering and Exhibit phases of the 62nd Semiannual Convention, which made it 
without question the most successful venture of its kind in Society history. 
Largely through his efforts the exhibitors, theater architects, and equipment 
manufacturers were informed of the Society's interest in the engineering aspects 
of theater design, construction, and maintenance. In turn, the Society will now 
be able to assess the things of this field more completely in the planning of future 
engineering work, as well as future convention programs. Until recently Mr. 
Frank was the New York Branch Manager of National Theater Supply, 356 West 
44th Street, New York 18, New York. 


Ralph B. Austrian joins the Board of Governors for the first time this year as 
Treasurer, but is by no means a newcomer to the Society. He joined in 1935 and 
has served on numerous committees during the intervening years. His major 
interest has been in the application of motion pictures to television, and we always 



think of him as an enthusiastic pioneer in this field, both in his previous associa- 
tions as President of RKO Television, Inc., and now as an executive with the 
Foote, Cone and Belding Advertising Agency, 270 Park Avenue, New York 17, 
New York. 


Alan W. Cook is now beginning his second two-year term as Governor of the 
Society and has a record of ten years of active participation in Society work, par- 
ticularly engineering committees. He can be reached at Ansco, Binghamton, 
New York. 

Lloyd T. Goldsmith became a member of the Board of Governors for the first 
time this year after a career of distinguished service to the motion picture indus- 
try and the Military Photographic Services. During the war he served as Direc- 
tor of the Army's Photographic Engineering Laboratory and, in addition, was 
Chairman of Z52, the War Committee on Photography, which, more than any 
other single factor, was responsible for developing the industry's vigorous inter- 
est in wartime Standards and in programs of quality improvement that followed. 
His address is Warner Bros. Pictures, Inc., Burbank, California. 

Paul J. Larsen has been a member of the Board of Governors for many years 
and this year begins another two-year term in the office of Governor. As Chair- 
man of the Society's Television Projection Practice Committee, Mr. Larsen's 
name has become synonymous with theater television because of his excellent 
work in the preparation and presentation in 1945 and 1946 of statements before 
the Federal Communications Commission requesting frequency allocations for 
theater television use. The purpose of his appearance before the FCC was to 
prevent the imminent reallocation of frequencies in the radio spectrum from ex- 
cluding their use by the motion picture industry for theater television at some 
future date, if the industry felt at that time that such a development was desir- 
able. Mr. Larsen has recently terminated his previous association with the De- 
partment of the Navy at Johns Hopkins University and is now Associate Director, 
Los Alamos Laboratory, University of California, Albuquerque, New Mexico. 

Gordon E. Sawyer has been a member of the Pacific Coast Board of Managers 
and has been most active in the affairs of the Society for many years. He is also a 
member of the Motion Picture Research Council and has aided in the co-ordinated 
activity of the Research Council and the Society. Mr. Sawyer is Director of 
Recording at the Samuel Goldwyn Studios in Hollywood, California. 

Atlantic Coast Section 

William H. Rivers, Chairman, assumed that office and thus became an ex- 
officio member of the Board of Governors on January 1 of this year. Together 
with the Board of Managers, he has planned an interesting program of Section 
Meetings for the current year. Mr. Rivers served in the Army Signal Corps 
during the war and then rejoined the Motion Picture Film Department of the 
Eastman Kodak Company, Room 626, 342 Madison Avenue, New York 17, 
New York. 


Edward Schmidt, Secretary-Treasurer, has been interested in the work of the 
SMPE for some time and this year holds his first Society office. He is with the 
Photo Products Department of the E. I. du Pont de Nemours and Co., Inc., 350 
Fifth Avenue, New York 1, New York. 

Midwest Section 

R. T. Van Niman, Chairman and ex-officio member of the Board of Governors, 
is experienced in Midwest Section affairs. The major part of organizing the 
Papers Program for the Society's 61st Semiannual Convention in Chicago in May, 
1947, was done very capably by Mr. Van Niman, and his enthusiastic interest in 
the SMPE will fit him well for his new job. He may be reached at Motiograph, 
4431 W. Lake Street, Chicago 24, Illinois. 

George W. Colburn, Secretary-Treasurer, is well known to many members of 
the Society in the Chicago area and beyond. This year he holds his first Society 
office. He is President of George Colburn Laboratory, Inc., 164 N. Wacker Drive, 
Chicago 6, Illinois. 

Pacific Coast Section 

Sidney P. Solow, Chairman, has been active in West Coast Section activities 
for years, having been on the Board of Managers previously and a member of 
several committees. He is now an ex-officio member of the Board of Governors, 
and in addition, is Chairman of the Local Arrangements Committee for the 63rd 
Semiannual Convention to be held in Santa Monica, California, May 17-21, 1948. 
He is with Consolidated Film Industries, Inc., 959 Seward Street, Hollywood, 

G. R. Crane, Secretary-Treasurer, is one of the younger, more active partici- 
pants in Pacific Coast Society affairs, having served on several committees 
and gained recognition from his associates. He is with the Hollywood Office of 
Electrical Research Products Division of Western Electric Company, 6601 Ro- 
maine Street, Hollywood 38, California. 

Student Chapter 

(University of Southern California) 

Thomas Gavey, Chairman, is a graduate student at the University of Southern 
California in the Cinema Department. He not only has been active in the forma- 
tion of the Student Chapter at the University but also for some time has been an 
active student member of the Society. Mr. Gavey's address is 1046 North Ridge- 
wood Place, Los Angeles. 

John Barnwell, Secretary-Treasurer, is a graduate student in the Cinema De- 
partment at the University of Southern California and along with Mr. Gavey was 
instrumental in the solicitation of student memberships for the establishment of a 
chapter at the University. Mr. Barnwell's address is Cinema Department, Uni- 
versity of Southern California, University Park, Los Angeles, California. 


1948 Nominations 

The 1948 Nominating Committee, as appointed by the President of the Society, 
was confirmed by the Board of Governors at its January meeting. The members 

40 Charles Street 
Binghamton, New York 


18 Cameron PI. 2237 Mandeville Canyon Road 

New Rochelle, N. Y. Los Angeles 24, California 


Warner Bros. Pictures, Inc. RCA Victor Division 

Sound Department Radio Corporation of America 

Burbank, California Engineering Products Department 10-4 

EMERY HUSE Camden, New Jersey 

Eastman Kodak Company K. F. MORGAN 

6706 Santa Monica Blvd. Electrical Research Products Division 

Hollywood, California 6601 Romaine 

PAULJ.LARSEN Los Angeles, Calif. 

Los Alamos Laboratory M. G. TOWNSLEY 

University of California 7100 McCormick Road 

Albuquerque, New Mexico Chicago 45, Illinois 

All voting members of the Society who wish to submit recommendations for 
candidates to be considered by the Committee as possible nominees, are re- 
quested to correspond directly with the Chairman or any of the members of the 
Nominating Committee. Active, Fellow, or Honorary Members are authorized 
to make these suggestions which must be in the hands of the Committee prior to 
May 1, 1948. 

There will be ten vacancies on the Board of Governors as of January 1, 1949, 
which must be filled. Those members of the Board whose terms of office expire are : 

President LOREN L. RYDER Governor JOHN W. BOYLE 

Executive Vice- 


Editorial Vice- 


Convention Vice- 

Secretary . G. TOEL LORANCE Governor HOLLIS W. MOYSE 


The recommendations of the Nominating Committee will be submitted to the 
Board of Governors for approval at the July meeting. The ballots will then be 
prepared and mailed to the voting members of the Society forty days prior to the 
Annual Meeting of the Society which is always the opening business session of the 
Fall Convention. This year it falls on Monday, October 25, and the Convention 
will be held at the Statler Hotel in Washington, D. C. 

E. ALLAN WILLIFOBD, Chairman, Nominating Committee 

Atlantic Coast Section 

The engineering data on the new RCA 16-mm recording channel were presented 
to the Atlantic Coast Section at its January 21 meeting by Everett Miller, 
RCA's technical supervisor in New York. The recording system, as a whole, 
was described in general, and a paper was read, dealing with the film recorder 
in particular. A 16-mm print of the Academy test reel was run to permit 
listeners to hear something standard and of known quality on the RCA re- 
producing system. Thereafter, various samples of films recorded on the new 
16-mm recorder were presented. These samples were used to show the rela- 
tionships between prints made from a negative, and direct positives processed 
for optimum image. There were also comparisons made between prints made 
from negatives, and Kodachrome prints made from direct positives. There was 
exhibited at the meeting the new RCA 16-mm film phonograph. Mr. Miller 
presented some engineering data and discussed the performance of this device. 
Thereafter, the meeting was opened for general discussion. 

ASA Appoints Vice-Admiral Hussey as 
Administrative Head 

Vice- Admiral George F. Hussey, Jr., United States Navy (retired), wartime 
Chief of the Navy's Bureau of Ordnance, recently joined the staff of the American 
Standards Association, and on January 1 assumed the duties of administrative 
head of that organization. Mr. Cyril Ainsworth, who for a number of years has 
been in charge of the technical activities of the ASA, will serve with Vice- Admiral 
Hussey as director of operations of the ASA staff. 

In accepting the appointment, Admiral Hussey will take over the adminis- 
trative responsibilities from Dr. P. G. Agnew, one of the world's foremost au- 
thorities on standardization. Dr. Agnew has served the ASA as secretary and 
head of the staff for the past 28 years, and will continue his service to the organi- 
zation as Consultant. 

As head of the Bureau of Ordnance, Admiral Hussey was responsible for its 
co-operation with industry and with other government departments on standards 
of mutual concern. In his new capacity, he will assist in co-ordinating the joint 
efforts of the interested bodies in many phases of standardization. 

At present, almost four hundred projects are being carried on under ASA pro- 
cedures, and the Association expects to increase its activities, under Admiral 
Hussey and Mr. Ainsworth, to approximately three times the volume of the 
largest prewar year. 


Inter-Society Color Council 

Members of the Society of Motion Picture Engineers have been cordially in- 
vited to attend the 17th Annual Meeting of the Inter-Society Color Council 
which will be held at the Hotel Pennsylvania in New York City on March 2 and 
3, 1948. Since the Society is one of the fourteen member bodies of the Council, 
it is hoped that as many of our members who are able will attend this meeting. 

A copy of the final program notice may be obtained by writing to: WALTER C. 
GRANVILLE, Chairman, Program Committee, Container Corporation of America, 
38 South Dearborn St., Chicago 3, Illinois. 

The preliminary program is given below. 

Tuesday, March 2, 1948 Conference Room 2 

10:00 A.M. DISCUSSION SESSION. Reports from subcommittees studying prob- 
lems on which the Council is currently working: 
Problem 2. Color Names. (Revision) D. B. Judd, Ch. 

6. Survey of Color Terms. S. M. Newhall, Ch. 

7. Survey of Color Specifications. W. C. Granville, Ch. 

10. Color Aptitude Test. F. L. Dimmick and C. E. 

Foss, Co-Ch. 

11. Color Blindness Studies. D. B. Judd and LeGrand 

Hardy, Co-Ch. 

12. Illuminating and Viewing Conditions in the Colorime- 

try of Reflecting Materials, D. B. Judd, Ch. 

13. The Illuminant in Textile Color Matching. D. Nicker- 

son, Ch. 

14. Single Number Specifications for Transparent Stand- 

ards. R. H. Osborn, Ch. 
2:00 P.M. DISCUSSION SESSION (Continued) 

Wednesday, March 3, 1948 Manhattan Room 

9: 30 A.M. COLOR CO-ORDINATION IN INDUSTRY. Discussed by members of the 
Inter-Society Color Council. 


University of Cincinnati, Cincinnati, Ohio 

In the spring of 1946 a project was established at the University 
of Cincinnati Research Foundation to develop a co-ordinated color 
scheme for prefabricated houses. The color scheme was developed 
with the aid of a mechanical color space, a model of which will be 
shown and discussed. 


Faber Birren, New York, N. Y. 

Functional color offers one of the newest and most gratifying 
fields of endeavor. Because of its importance to industrial relations 
and human welfare, the benefits should be vastly extended. The 
application of this idea to industrial plants will be discussed. 



Meyer, New York, N. Y. 

This Council was formed to select a group of colors to serve as the 
basis for color correlation in all branches of the home furnishings 

N. Creston Dons, Libby-Owens-Ford, Toledo, Ohio 

Color research, aimed at combating worker eyestrain in the 
manufacture of precision glass, resulted in the development and 
standardization of the "daylight" principle of maintenance paint- 
ing in all Libby-Owens-Ford plants. A program of color engineer- 
ing was inaugurated to improve working conditions, create better 
industrial relations, and surround the worker with an environment 
which makes for better public relations between him, his fellow 
workers, and his neighbors. Color engineering thus becomes the 
catalyst which bonds several harmonious conditions into one condi- 
tion which we may learn to know as "Human Relations". 

Monsanto Chemical Company, Springfield, Massachusetts 

Color laboratories for large manufacturers of colored plastics 
develop thousands of color matches each year. Too often their ef- 
forts seem directed to prove the infinity of color in plastics. But far 
short of this is a minimum number of colors which will satisfy most 
requirements. To find this number most quickly and economically, 
it is helpful to file color matches by their color. A three-dimensional 
file based on colorimetric specifications of the International Com- 
mission on Illumination is proving useful in this work. Properly 
organized, it can show quickly an array of the colors already de- 
veloped, one of which may serve a new requirement. 

Lucille Knoche, Chicago, Illinois 

A study of merchandise color co-ordination for Montgomery Ward 
and Company was made in the fashion and home furnishing fields. 
The problem was approached through consumer surveys on color 
preferences in various lines, analyses of color sales for past years 
and a belief in the creation of multiple sales through color co-ordina- 
tion of related lines. The results and applications of these surveys 
will be presented. 
THE 1947 FRAZER-MANHATTAN. Carl Spencer, Detroit, Michigan 

Requirements of color co-ordination and scope of materials in- 
volved in Frazer-Manhattan car styling as built in mass-production 
quantities will be discussed. Practical methods established in 
maintaining color control in the production of Frazer-Manhattan 
cars include control of viewing conditions, spinning-disk analysis 
and Munsell specifications. In order to allow maximum creative 
development, color-effect analysis is used to supplement basic color 


lor, Philadelphia, Pennsylvania 
The color plan for W. T. Grant Company will be described and its 

application by the sources of supply, by the buying staff, and by 

the retail stores will be presented. 

International Commission on Illumination, 
Colorimetry, and Artificial Daylight 

For those members of the Society of Motion Picture Engineers who have a 
fundamental interest in the science of colorimetry as well as in the current pro- 
grams for developing international agreement on colorimetry standards, specifica- 
tions, and terminology, the following introduction and condensed questionnaire are 
presented here. 

The Society is a member body of the Inter-Society Color Council and has the 
following delegates to represent the motion picture industry's interests in this 
important field: 

R. M. EVANS, Chairman 



The Inter-Society Council, as its name implies, serves to correlate the views, at- 
titudes, and recommendations of all interested groups as individuals in this coun- 
try for the use of the United States National Committee of the International 
Commission on Illumination. * 


The International Commission on Illumination (I.C.I.) is planning to resume 
its activities interrupted by the war. The last meeting was at Scheveningen, Hol- 
land, in 1939. The next one is scheduled for Paris in July, 1948. 

The I.C.I, operates through national committees of the respective member coun- 
tries comprising the Commission, and through numerous technical committees 
covering a wide variety of subjects in photometry and lighting. Each national 
committee sets up a technical committee for each subject in which it is suf- 
ficiently interested. For each of these subjects the I.C.I, assigns the Secretariat 
to some one country. Each national committee selects the personnel of its 
technical committees. 

For Technical Committee No. 7, Colorimetry and Artificial Daylight, the 
Secretariat was assigned to the United States and the U. S. National Committee 
appointed the following committee: 

K. S. GIBSON, Chairman 



One of the duties of the secretariat committee is to obtain information on the 
assigned subject from the various countries and to prepare recommendations or 
summaries for the next meeting of the I.C.I. Dr. Gibson, chairman of the 
committee, would appreciate receiving any available information on the sub- 
jects as soon as possible. 


The committee desires to summarize American opinion on colorimetry and 
artificial daylight as well as foreign opinion. The subject of color is of increasing 
interest to motion picture engineers, and the secretariat committee will be very 
glad to receive comments on the questionnaire. 

Copies of the complete questionnaire are available for distribution to anyone 
who wishes to assist the American Technical Committee to formulate American 
opinion by sending in commments. Address requests to Dr. K. S. Gibson, Chair- 
man, U. S. Technical Committee No. 7 of the I.C.I., National Bureau of Stand- 
ards, Washington 25, D. C. 

1. Proposed Standard Illuminant E 

At the tenth session of the I.C.I, at Scheveningen in 1939 it was recommended 
that the national committees study the advantages which the use of standard il- 
luminant E would present as a substitute for standards illuminants B and C, to 
represent a generally satisfactory artificial daylight, and to serve as a common 
basis whenever it is necessary to characterize the color of an object for the pur- 
pose of international comparisons. 

A. The proposed new illuminant E (x = y = z = 0.3333) is realized by com- 
bining I.C.I, illuminant A (2848 degrees Kelvin) with a specified Davis-Gibson 
filter, in a manner similar to the realization of illuminants B and C. Many in the 
United States are opposed to the substitution of the proposed illuminant E for 
standard illuminant C in the colorimetry of nonself-luminous objects. 

Do you favor or disfavor the adoption of a new standard illuminant E for the 
colorimetry of nonself-luminous objects? 

B. In the colorimetry of light sources there appears to be some advantage in 
the use of the point (x w = y w = z w = 0.3333) representing the equi-energy source 
as the achromatic point for the determination of dominant wavelength and 

Do you favor the adoption of illuminant E for the achromatic point in the 
colorimetry of light sources, or would you prefer that the hypothetical equi-energy 
source be used for this purpose? 

2. Colorimetric Purity 

(A second recommendation of the 1939 session of the I.C.I, relates to a defini- 
tion of colorimetric purity. The present questionnaire asks for comments on a 
suggested revision of this definition. The suggested revision uses the spectrum 
locus and the purple boundary of the mixture diagram for unit colorimetric 
purity. It uses two achromatic points. For self-luminous bodies the point 
representing the proposed standard illuminants E (x = y = z l /a) is suggested; 
and for light reflected from objects the point representing the illuminant is sug- 
gested. Since the chromatic and achromatic components are to be evaluated 
in terms of luminance this definition agrees with that given in the OSA colori- 
roetry report, J. Opt. Soc. Amer., vol. 34, p. 669; 1944.) 

3. Standard Observer 

Do you have any scientific evidence or practical experiences that indicate 
that the standard observer fails to represent normal observers satisfactorily? 


4. Standard Illuminants 

A. In view of the possible influence of ultraviolet irradiation on the colors of 
fluorescent samples, do you believe that the definition of standard illuminants A, 
B, and C should be made more precise in regard to the ultraviolet? 

B. In view of the growing use of fluorescent materials and of light sources that 
are rich in ultraviolet energy, do you believe that an additional standard illumi- 
nant different from illuminants A, B, and C, by having relatively more ultraviolet 
energy, should be established? 

5. Illuminant for Color Matching 

For commercial color matching, is it your practice to use chiefly (a) one or 
other of the standard illuminants A, B, or C, (6) some other combination of filter 
with an incandescent lamp, (c) some fluorescent lamp, (d) some phase of natural 
daylight, or (e) some other light source? 

6. Specification of Color-Rendering Properties 

Has any recognized method been developed to indicate the degree to which 
artificial daylight produces a rendering of object colors in conformity to that 
. produced bv one of the standard illuminants? 

7. Color Discrimination 

The various National Committees are requested to supply such data on dis- 
criminability of various colors and on ways of distorting the XYZ lattice to yield 
approximately uniform color scales as have been obtained since 1939. These 
data will be summarized by the U. S. Committee for consideration at the 1948 

8. Color Terminology 

It is recognized by the U. S. Committee that discussion of color terms at the 
1948 meetings of the I.C.I, might have the very desirable result that divergent 
usage in the various nations would be reduced, or even eliminated for some color 
concepts. To keep the discussion within reasonable bounds, however, it is 
proposed to limit discussion to the nine psychophysical and five psychological 
concepts defined below: (There follow definitions of the psychophysical terms: 
color, luminance, directional luminous reflectance, dominant wavelength, com- 
plementary wavelength, purity, chromaticity, tristimulus values, and chroma- 
ticity co-ordinates; and of the psychological terms: brightness, lightness, hue, 
saturation, and chromaticness. Comments on the definitions and on the terms 
used for the concepts are requested.) 

Society of 

Motion Picture Engineers 

342 MADISON AVENUE NEW YORK 17, N. Y. TEL. Mu 2-2185 


Atlantic Coast 

Chairman Secretary-Treasurer 

William H. Rivers Edward Schmidt 

Eastman Kodak Co. E. I. du Pont de Nemours & Co. 

342 Madison Ave. 350 Fifth Ave. 

New York 17, N. Y. New York 1, N. \. 


Chairman Secretary-Treasurer 

R. T. Van Niman George W. Colburn 

Motiograph George W. Colburn Laboratory 

4431 W. Lake St. 164 N. Wacker Dr. 

Chicago 24, 111. Chicago 6, 111. 

Pacific Coast 

Chairman Secretary-Treasurer 

S. P. Solow G. R. Crane 

Consolidated Film Industries 212 24 St. 

959 Seward Santa Monica, Calif. 
Hollywood, Calif. 

Student Chapter 
University of Southern Calforoia 

Chairman Secretary-Treasurer 

Thomas Gavey John Barn well 

1046 N. Ridgewood PL University of Southern 

Hollywood 38, Calif. California 

Los Angeles, Calif. 

Office Staff New York 


Boyce Nemec Margaret C. Kelly 


Thomas F. Lo Giudice Helen M. Stote 

Dorothy Johnson Helen Long 

Beatrice Melican 


of the 

Society of Motion Picture Engineers 



Wartime Naval Photography of the Electronic Image 

High-Speed Motion Pictures with Synchronized Multiflash 

Lighting R. A. ANDERSON AND W. T. WHELAN 199 

Electronic Flashtube Illumination for Specialized Motion 

Picture Photography HENRY M. LESTER 208 

Synthetic Sound on Film 


Industrial Control Applied to the Projection Room 


Review of SMPE Work ,on Screen Brightness 254 

Report of Screen-Brightness Committee 260 

Report of ASA Committee on Standards for Motion Pictures, 

Z22 274 

Five Recent American Standards on Motion Pictures 282 

Melvin E. Gillette. 290 

63rd Semiannual Convention 291 

Section Officers 296 

1948 Nominations 297 

Section Meetings , 298 

Correction 298 

Book Reviews: 

"The Architects Manual of Engineered Sound Systems," 

Reviewed by C. S. Perkins 299 

"Television," Volumes III and IV, Reviewed by Pierre Mertz 299 

Current Literature 301 

Journal Exchanges 302 


Chairman Editor Chairman 

Board of Editors Papers Committee 

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their annual membership dues; single copies, $1.25. Order from the Society's general office. 
A discount of ten per cent is allowed to accredited agencies on orders for subscriptions and 
single copies. Published monthly at Easton, Pa., by the Society of Motion Picture Engineers, 
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342 Madison Ave., New York 17, N. Y. Entered as second-class matter January 15, 1930, 
at the Post Office at Easton, Pa. under the Act of March 3, 1879. 

Copyright, 1948, by the Society of Motion Picture Engineers, Inc. Permission to republish 
material from the JOURNAL must be obtained in writing from the General Office of the Society. 
Copyright under International Copyright Convention and Pan-American Convention. The 
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Society of 

Motion Picture Engineers 

342 MADISON AVENUE NEW YORK 17, N. Y. TEL. Mu 2-2185 



Loren L. Ryder Clyde R. Keith 

5451 Marathon St. 233 Broadway 

Hollywood 38, Calif. New York 7, N. Y. 

Donald E. Hyndman William C. Kunzmann 

342 Madison Ave. Box 6087 

New York 17, N. Y. Cleveland, Ohio 

Earl I. Sponable G. T. Lorance 

460 West 54 St. 63 Bedford Rd. 

New York 19, N. Y. Pleasantville, N. Y. 



John A. Maurer James Frank, Jr. 

37-0131 St. 18 Cameron PI. 

Long Island City 1, N. Y. New Rochelle, N. Y. 


Ralph B. Austrian 

247 Park Ave. 

New York 17, N. Y. 



John W. Boyle Robert M. Corbin Charles R. Daily 

1207 N. Mansfield Ave. 343 State St. 5451 Marathon St. 

Hollywood 38, Calif. Rochester 4, N. Y. Hollywood 38, Calif. 

David B. Joy Hollis W. Moyse 

30 E. 42 St. 6656 Santa Monica Blvd. 

New York 17, N. Y. Hollywood, Calif. 


William H. Rivers S. P. Solow R. T. Van Niman 

342 Madison Ave. 959 Seward 4431 W. Lake St 

New York 17, N. Y. Hollywood, Calif. Chicago, 111. 


Alan W. Cook Gordon E. Sawyer 

4 Druid PL Lloyd T. Goldsmith 857 N. Martel 

Binghampton, N. Y. Burbank, Calif. Hollywood, Calif. 

Paul J. Larsen 
Los Alamos Laboratory 
University of California 
Albuquerque, N. M. 

Section Chairmen and Secretary-Treasurers listed on page 296. 

Wartime Naval Photography 
of the Electronic Image* 



Summary In order to train new radar operators quickly and to teach 
experienced operators how to utilize the newer types of radar prior to in- 
stallation, the United States Naval Photographic Science Laboratory under- 
took the investigation of cathode-ray-tube motion picture photography on a 
production basis. Its methods, as described here, form the basis for the 
present United States Navy advances in this type of photography. 

DURING the early days of World War II, radar was becoming 
widely accepted and depended upon by the United States Fleet. 
In combat, unit commanders realized that radar was a .powerful 
ally, and from their experiences and reports, a definite need became 
evident to institute a training program for personnel. This pro- 
gram was designed both to train new radar operators quickly and to 
teach experienced operators how to utilize the newer types of radar- 
prior to installation. 

The great bottleneck lay in instructing sizable personnel to inter- 
pret successfully the wide variety of signals appearing on such equip- 
ment and to keep operators abreast of the enemy's newest methods of 
jamming radar and confusing radar patterns. Obviously, it was not 
always practicable or possible to demonstrate to students through 
actual operations the many signals and conditions which could and 
probably would be encountered. No lecture, pamphlet, or book can 
show, for instance, how to "read through" enemy jamming, yet still 
determine the range, bearing, and target angle of attacking aircraft; 
this task is accomplished easily and effectively only through the 
medium of motion pictures (Fig. 1). 

Accordingly, the United States Naval Photographic Science Labora- 
tory undertook the investigation of the virtually unexplored 'field of 
cathode-ray-tube motion picture photography on a production basis ; 
the results, photographed under actual operating conditions, were 
intended for incorporation in United States Naval training films. 

* Presented October 24, 1946, at the SMPE Convention in Hollywood; Bur- 
bank session. 



The methods as described herein were evolved during the war for 
wartime utilization and form the basis for present United States 
Naval advances in cathode-ray photography (Fig. 2). 

A study of the cathode-ray tube to be photographed is a critical 
part of the photographic procedure, and should be aimed at selecting 
a tube of maximum illumination output. Cathode-ray tubes, new 
and of the same make, may vary widely in brilliancy, a variation of 
60 per cent being not uncommon. The optimum tube of the group 
is selected and is used throughout the production unless its brilliance 
falls off substantially. It may be interesting to note that a given 

Fig. 1 Photographing the radar scope. 

tube when activated in two sets of the same make may give entirely 
different photographic results because of inherent variations of the 

The adjustments con trolling tube intensity and focus are of the 
utmost importance from the viewpoint of the cameraman. The opti- 
mum point of signal intensity for photographic purposes requires 
some denning. In general, an operator views his radar scope with 
tube-illumination levels (gain) at a comparatively low point because 
of the increased contrast to the human eye. As tube intensity is in- 
creased and complete fluorescence of the scope is obtained, the signals 
are so diminished in contrast that the operator can no longer dis- 
tinguish them. The optimum photographic point has been deter- 
mined to lie just under the point where returning signals are slightly 


discernible to the operator through the fairly luminous scope. When 
this optimum photographic point has been determined by test, its 
future determination must remain dependent upon the cameraman's 
eye. Merely marking the original control settings does not neces- 
sarily assure the same intensity from day to day. It has proved im- 
practical to meter tubes either electrically or photoelectrically. 

To the eye, a cathode-ray-tube fluoroscope assumes its greatest 
brilliance when viewed in surrounding darkness. It is quite natural 

Fig. 2 =A typical plan-position-indicator radar scope. 

to assume that, because of the contrast noted by the eye, photography 
should be carried out under similar conditions. Repeated experi- 
ments and tests have shown that this assumption is incorrect. It was 
found that if a certain measured amount of light is projected or re- 
flected on the face of the tube, the quality of the photographed image 
is considerably improved. The resulting increase in image density 
caused by the incident light on the tube face can be explained in part 
on the basis of threshold exposure; if the light used approximates 
that required "to create a threshold exposure for the particular emul- 
sion used and the processing to be applied, the additional exposure 
produced from the luminous tube is moved farther up the toe of the 


sensitometric curve toward the straight line and usable region. Thus, 
a small, measured amount of incident light ("threshold" light) on the 
face of the tube is one of the most critical and important factors in radar 
motion picture photography. 

In general, one or two heavily diffused lights are placed some dis- 
tance from the tube face in such a position that unwanted shadow, 
hot spots, and reflections are avoided. The light may be projected 
directly on the tube face or bounced from a soft reflector. In any 
case, it is essential that the light be soft, even, and flat. The intensity 
of the threshold light may be controlled by diffusion, distance, or 
rheostat, and may be measured by means of the No. 603 Weston 
meter. Depending upon emulsion speed, lens aperture, tube inten- 
sity, future processing, camera speed, and the horizontal and vertical 
angular incidence of the light itself, the intensity may range from y 4 
to l x /2 foot-candles, and possibly may even slightly exceed that 
range. The threshold light must be the only outside source of illumi- 
nation, and -should be high in ultraviolet. 

Cathode-ray tubes are usually covered with colored plastic filters, 
which are removed during photography. If range lines or other indi- 
cating lines are desired on the tube face, a new cover of thin, clear 
plastic with the appropriate markings may be used. 

Few concrete and unqualified statements can be made concerning 
camera speeds. It was generally desirable to stay as close to 24 
frames per second as possible. At times, it may be possible to photo- 
graph at slightly lower speed and accordingly greater exposure if 
screen-speed distortion- does not preclude its use. In some instances, 
the frequency of short persistent tubes is such as to produce har- 
monics with the camera shutter resulting in either partial or complete 
loss of exposure. It is absolutely necessary that the camera shutter 
turn at such speed as to prevent harmonics. Determining whether 
or not a serious harmonic exists may be done mathematically, em- 
ploying a relationship between tube frequency, shutter opening in 
degrees, and shutter speed, or by straightforward visual means. If 
"blackouts" do not occur when watched through the. camera's focus- 
ing eyepiece with the camera in operation (unloaded), and if signals 
appear normal and undistorted, there is no harmonic. In most cases, 
if the camera speed is slightly lowered, harmonics, noted at normal 
speed, will disappear. 

If it appears impossible either to underspeed the camera without 
causing serious distortion, to change tube frequency, or have the nega- 


tive double or otherwise optically printed, one course is open: the 
use of a larger, shutter opening. A thorough study was made, and 
after a survey of all available cameras it was determined that an 
Akeley Standard 35-mm camera was most readily adaptable to this 
change. Gerald J. Badgley of the Naval Photographic Science Lab- 
oratory was successful in rebuilding an Akeley Standard to obtain a 
shutter opening of 291 degrees in comparison to the usual 170 degree 
shutter opening. This represented an increase of 121 degrees or 
approximately 71 per cent increase in exposure. Spatial and linear 

Fig. 3 Lighting and camera setup for photographing a cath- 
ode-ray tube using an Akeley single-system 35-mm camera. 

distortions are occasionally noted, however, in the use of such shutter 
openings (Fig.3) . In general, the standard precision movement 35-mm 
motion picture cameras, such as the Mitchell or the Bell and Howell, 
can be used to photograph the great majority of radar scopes. . 

Fifty-millimeter Zeiss Sonar lenses with maximum aperture of 
//1. 5 were generally used in the cameras. Under some conditions, 
a 75-mm Zeiss Biotar lens proved useful. Almost invariably, the 
lenses were operated at full aperture. While any good lens of //1. 5 
or better is satisfactory, it should be remembered that the lenses of 
.some manufacturers are ' overrated, based on transmission. The 
lenses were later coated with magnesium-fluoride coatings applied to 


all surfaces. Transmission was thereby increased approximately 18 
per cent, and definite results were observed in increased shadow detail 
and increased over-all sharpness of the signal images. Persistence of 
the signal image was improved, with diminution of flares and ghosts 
usually encountered when photographing a source of incident light 
such as a cathode-ray tube. The coatings were not of the usual com- 
mercial type, but were specially applied by the Optical Section, Navy 
Yard, Washington, D. C. - 

The possible effectiveness of filters was given extensive testing, and 
their use appeared to be inadvisable, having the major disadvantage 
of reducing exposure. The desired feature of a filter was to reduce 
the contrast between an overbright trace line and the signal. Ex- 
perience has shown that no filters currently available are sufficiently 
sharp cutting to hold down the trace and transmit the signal. 

In nearly every case, panchromatic film with a Weston rating of 50, 
such as Plus-X, was the preferred emulsion, irrespective of fluoroscope 
screen color. It reacted to the necessary type of processing better 
than any faster emulsion. Films of higher-speed ratings were also 
successful but had a proportional increase in graininess. When ex- 
treme speed was necessary, Eastman Fluorographic was used, al- 
though pronounced grain and subsequent loss in quality were evident. 
Theoretically, it would appear desirable to adopt an emulsion high in 
green and blue sensitivity to meet the color of most cathode-ray tubes ; 
however, this consideration does not seem to be as critical as originally 
supposed-. If a choice in the color of fluorescence is possible, that 
most closely approaching white is desirable. 

Machine processing of the negatives was used exclusively. In 
most large production processing laboratories, only two developers 
are available, positive and negative. It was hardly possible under 
wartime conditions to reserve one entire machine for special develop- 
ing solutions. If the photographic techniques are geared to the 
available development, with suitable adjustments in development 
time and selection of printer light, special developing solutions are 
not considered necessary. Tests with developers not adapted to 
machine processing did not show any gains commensurate with their 
disadvantages. Test results pointed markedly to the superiority of 
the positive-type developer for processing radar-scope negatives. 

In most cases, positive-type development of 8 to 12 minutes offers 
a negative which will print near the middle of the scale. Increased 
development appears to result only in increased over-all fog. Forced 




development in a standard negative-type developer did - not yield 
comparably desirable results. Fig. 4 shows a sensitometric compari- 
son between a comparatively fast emulsion and Plus-X in both nega- 
tive and positive developer at various developer times. It may be 
noted that Plus-X reacted more desirably than any other fast emul- 
sion tested. It may also be noted that the positive-type development 
brought about the desired advantages of increased gamma, apparent 
emulsion speed, and a heavier eleventh (star) step density, without 
undue increase in fog (Figs. 4 and 5) . 



10 MIN. 15 MIN. 





Fig. 4 Effect of development on gamma and effective speed for Plus-X and 
Tri-X panchromatic film. 

The critical nature of radar-scope photography demands that both 
the tests and the entire production be carried on with film stock of the 
same emulsion number. Different emulsion numbers may yield 
slightly different results even when handled identically. When work 
is only slightly above the film threshold point, such small differences 
may produce drastically different results. 

As an interesting side light to the problem of cathode-ray-tube 
photography, both hypersensitization and intensification for large- 
scale processes were attempted, and some interesting results were to 
be noted. In general, the mercury-vapor treatment of stock will 
increase film speed approximately one stop. The treatment of 




substantial production footage presents many problems, however. 
Such factors as the influence of the treatment on various emulsions, the 
age of the film, differing intervals between photography and treatment 
remain to be answered. It was felt that the many variables which 
are to be encountered in hypersensitization did not allow its use on 
large-scale production footage. To date, no radar-scope photography 
has required its use. Brief experiments indicate that intensifica- 
tion probably holds more promise to produce better negatives than hy- 
persensitization. In some cases, highly complicated photography of 







Fig. 5 Effect of development on .eleventh-step density and fog for Plus-X 
and Tri-X panchromatic film. 

the cathode-ray-tube signals were best presented by animation or a 
combination of animation and photography. For explanatory pur- 
poses in training films, animated signals offered the greatest clarity 
because they can be made uncomplicated by noise and secondary 
signals which frequently appear on an actual scope. 

The methods and equipment described in this paper are not neces- 
sarily the ultimate in perfection, but they were the most satisfactory 
solution to the production motion picture photography of cathode- 
ray-tube signals during the war. It is emphasized that some tubes 
and signals pose no photographic difficulties; however, the cases 
where simple photography is possible should not be taken as the cri- 
terion for use in the many complicated cases. 


It is the experience of the Uilited States Naval Photographic Serv- 
ice that there is no secret magic involved in the satisfactory photog- 
raphy of cathode-ray tubes. Success is dependent upon the exacting 
application of the best photographic practices and the correlation of 
all standard photographic principles, plus some knowledge of the 
electronics involved. The postwar fields of cathode-ray photography 
are unlimited, and the basic principles as described herein doubtless 
will be used in the everincreasing use of photography in the fields 
of radar, loran, and television. 


The authors wish to acknowledge and thank the following men 
whose foresight and photographic skill were responsible for the suc- 
cessful completion of radar motion picture photography, and whose 
meticulous data and reports were invaluable in the preparation of this 
paper: Lieutenant Commander Donald Hooper, Lieutenant George 
C. Maloney, Lieutenant Carlton G. Murray, Lieutenant Winston 
Hoke, and Chief Specialist L. Riley, all of the United States Naval 


MR. JOHN CRABTREE: What is the effect of this supplementary exposure on 
the front of the screen image? Does it not lower the brightness of the contrast 
although it gives you effectively more speed? 

LIEUT. WINSTON HOKE : I would not say that it increased the over-all contrast of 
the image, but it did pick up those very faint images, the faintest of which were 
our most serious problem. One point not covered in the paper was the various 
sweep speeds which were available on radar scopes. In almost all cases, we had 
sufficient photographic brightness. Our problem in that connection was one of 
timing, but we got down to the first and second and third sweep speeds, and each 
switch reduced the brilliancy about one tenth. We had a serious problem in the 
second and third speed. The foglight technique was rather striking on our tests 
in that, on occasion, in starting the camera the operator was blocking the light, 
and when his shadow cleared the face of the scope, the signal seemed to spring 
out with the foglight as it fell. I cannot say that it had any effect on the over-all 
gamma. It certainly did not tend to shorten the image. 

The approach to the problem as presented in the paper is a little more formal 
than that which was actually accomplished. We were there with our two hands 
and the few cameras available, and the problem came through of photographing 
initially with the loran scope. It developed on tests we not only had a particu- 
lar problem, but one of serious exposure in the second and third sweep speeds. 
I am not sure about the third, but I believe there were at least two, maybe three. 
We did not attempt to go too far into basic research in the problem, since there 
was not time. It was simply a case of using known techniques and squeezing 
the most out of them that we could under wartime conditions. The co-operation 


and very close attention given to us by Wilson Leahe, who was in charge of 
processing, very greatly aided this work. It was decided in conference with 
Mr. Leahe that we would not try to advance too far into special developers, be- 
cause his facilities were limited, and if we could get a possible solution with de- 
velopers that were currently in production use, we could handle our photography 
on a production basis. As the ultimate goal, I am sure this work will be sur- 
passed, or has been now; but it is an interesting story of what could be done or 
was done by squeezing the most effect we could get from forced development and 
from the use of the foglight or threshold exposure. 

MR. HARRY R. LUBCKE: Why were your lights incandescent? Were they 
provided with niters? What was the nature of the exposing lights? 

LIEUT. HOKE : The lights were incandescent. 

Mr. BOYLE : In the later stages of the war I was out at 20th Air Force and we 
had problems involving much the same as you did, only they were all airborne 
problems, that of taking the photographic image off of the airborne radar on B-29's 
and the problem there was to fly B-29's reconnaissance missions over Japan and 
over a planned route and make photographs of the scope and bring them back and 
brief whole groups from the basis of that reconnaissance flight. However, we 
had quite a bit of difficulty, and I am interested to find out from you whether this 
idea of yours was applied actually in operations with Navy airborne equipment. 
It seems rather large and bulky as shown here, and I just wondered whether you 
were using that tor operational briefing. 

LIEUT. HOKE : We had cameras mounted in the aircraft on all of the airborne 
equipment which was sent to us for photographic purposes. The nature of our 
work there was in connection with getting training-film problems on the screen, 
and I regret I do not have the reference here as to plane types, or radar types that 
we photographed, but we did fly in torpedo bombers. I took quite a jaunt in a 
PBM over the Atlantic, and on the trip we did not use the bulky equipment that 
you see. We did, however, use a full-sized motion picture camera. One 
of the cameras would carry the bulk of our work. It had about a 230-degree 
shutter that was used on the major part of our loran photography. It permitted 
us to use a photographing speed of approximately 17 pictures per second. As- 
suming you have a radar sweep speed of 25 cycles, if you tried to photograph 
that with a 170-degree camera reduced to approximately 12 pictures per second, 
and speeded up the action two to one, which is quite noticeable on the screen, it 
therefore decreases its training value. If you can squeeze it to 230, you can get 
close to 18 pictures per second and the eye and mind are much more willing to 
accept 18 pictures per second speed for training purposes. We later found one 
scope with a speed of, I believe, 10 cycles per second. That one was difficult. 
That was with the standard Akeley where we managed to get the 291 -degree 
shutter, and by photographing at approximately eight pictures per second, and 
double-printing each frame, we achieved a screen result of 16 pictures per second, 
which retained its training-screen value. But exposure was a very serious problem 
to us in this work, and the threshold light was an astonishing aid. I hardly be- 
lieved the results I saw. That is the photographic problem that caused us to 
request . the Research Developing Department to find us a hypersensitizing aid. 
Roy Deering, who was then in charge of that department, succeeded in doubling 
the speed of the film by his mercury treatments. However, it was rather awkward 
to use in any quantity, and since the pressure was not too great, we did not ac- 
tually use it to any large extent. 

High- Speed Motion Pictures with 
Synchronized Multiflash Lighting' 



Summary Equipment to synchronize a high-intensity flashlamp with a 
high-speed motion picture camera has been designed and built. The camera 
was a 16-mm, rotating-prism type and synchronization was accomplished by 
a brush-type contactor built into the camera. The electrical signal from the 
contactor was sent through a pulse-forming circuit to a trigger tube in the 
flashlamp circuit. The film speed was 1800 frames per second and the 
duration of each flash was about "one microsecond. Resolving-power tests 
made by photographing a one-foot disk revolving at 1500 revolutions per 
minute showed the marked superiority of flash-lighting over continuous light 
at these speeds. The resolving power measured for a rapidly moving object 
was doubled by the use of multiflash lighting, and, even in the case of a sta- 
tionary object, a 25 per cent increase was obtained. 


IN ORDER TO obtain maximum 'effectiveness in the photography of 
fast-moving objects, exposure time must be kept to a minimum. 
This is particularly true in the recording of high-speed motion pictures 
where both the object and film are in motion. The motion of the film 
may be partially compensated by the use of a rotating-prism-type 
shutter t which deflects the image so that it follows the motion of the 
film, thus reducing the blurring caused by longer exposure time. For 
very high speeds, however, it is desirable to employ multiflash lighting 
and rely. on the extremely brief duration of the flashes for timing ex- 
posures. 1 This paper describes the results obtained when a simple, 
multiflash lighting unit was synchronized with a high-speed motion 
picture camera. 


In addition to permitting increased definition in high-speed motion 
pictures, the brief flash durations obtained with multiflash lighting 
result in an increase in efficiency over incandescent lighting as regards 
the utilization of available light output. For instance, if, when using 

* Presented October 21, 1947, at the SMPE Convention in New York. 

f Commercially available cameras using a rotating-prism-type shutter are the 

Eastman High-Speed Camera, Type III, and the Western Electric "Fastax". 



incandescent lighting, the exposure time per frame is one fifth the time 
required for each frame to pass the camera lens,* then four fifths of 
the light energy required is wasted. With multiflash lighting, the 
camera shutter is open during the total duration of the flash and no 
light energy is cut off by the shutter. This results in an increase of 
efficiency by a factor of five. A second advantage of multiflash light- 
ing lies in the spectral distribution of its light output. 2 The light 
emitted by an argon- or xenon-filled flashtube lies mainly in the blue- 
violet region of the spectrum where high-speed photographic emul- 
sions are most sensitive. With incandescent lighting, the major part 
of the energy radiated lies in the red and infrared end of the spectrum 
and this is obviously inefficient for high-speed photographic work. 


In order to use multiflash lighting for motion pictures, some system 
of synchronizing the flashes with the camera speed is required so that 
the frames will be spaced properly on the films. It was considered de- 
sirable to design synchronization equipment for use with a rotating- 
prism-type camera so that this camera might be employed with mul- 
tiflash lighting when fine detail was required, but might also be used 
with a simple incandescent light source. The synchronization was 
accomplished by producing a signal, through a contactor on the cam- 
era, and sending this signal to the grid of a control tube. The control 
tube in turn operates the flashlamp. 

The performance of the Eastman Type III rotating-prism camera 
had proved to be so satisfactory with incandescent lighting that it was 
chosen for the adaptation of synchronization. Because of variation 
in the speed of the camera during the run, it was necessary to provide 
for synchronization over a range of frequencies. While an average 
speed of 1750 frames per second was sought, the actual camera speed 
during the usable portion of its run varied from 1600 to 1900 frames 
per second. .Synchronization was made available over a range of 
speeds from 1500 to 2000 frames per second. A contactor, consisting of 
nine radially located steel bars set into the side of a bakelite disk, was 
attached to the motor shaft of the camera as shown in Fig. 1. A 
brush was used to make contact with one of the steel bars each time 
the prism moved to its wide-open position. 

* Instruction booklets indicate that these are the relative times obtained with 
the Eastman Type III Camera. 


Fig. 2 (A) shows the idealized contactor signal which would result 
from a sharp, clean, make-and-break contact between the contactor 
bar and brush. Oscillographic examination of the contactor signal, 
however, showed this signal to be quite ragged because of vibration 
of the component parts of the contactor, and inductive and electro- 
static interference from the driving motor. Voltage spikes of an ampli- 
tude comparable to the desired signal voltage occurred at random, 
preventing synchronization of the system. Fig. 2(B) shows a sketch 
of the signal actually obtained. To remedy this condition, the inte- 

Fig. 1 Details of contactor mounted on motor shaft of 
camera showing nine radially located steel bars and brush. 

grating filter shown in Fig. 3 was added to the contactor circuit. A 
capacitor Ci charges through resistor RI during the make period of 
the contactor and discharges through resistor ^2 during the break. 
The resultant output signal is of the form sketched in Fig. 2(C). Af- 
ter the charge and discharge time-constants of the circuit were prop- 
erly adjusted for the desired camera speed, the contactor signal was 
found to be entirely satisfactory for more than fifty consecutive shots. 
The output signal from the contactor is fed directly to a pulse gen- 
erator which shapes the signal and increases its magnitude. The pulse 


generator is of the multivibrator type, having an output of 150 volts 
with a variable pulse width, and is readily synchronized with an input 
signal. A quick check may be made of the signal by putting ear- 
phones across the output of the pulse generator and starting the cam- 
era. If the apparatus is functioning properly, a musical note of rising 





Fig. 2 Sketches of ideal and actual contactor 




=- 90V 




500K^R2 TO 
Cl il > PULSE 



Fig. 3 Integrating filter circuit added to 
contactor circuit. 

pitch will be heard as the camera approaches operating speed. If the 
synchronization is faulty, the note is unmusical except for short, dis- 
connected bursts, and this condition can be corrected without the 
necessity of taking pictures. 


The conventional flashtube circuit, shown in Fig. 4, was used. A 
storage capacitor of one-tenth microfarad is charged to approximately 




8000 volts and discharged through the flashtube and a 4-C-35 hydro- 
gen thyratron. The capacitor is charged between flashes through the 
charging choke connected to a high- voltage power supply. Flash du- 
rations of about one microsecond are obtained with this circuit. 
The 4-C-35 hydrogen thyratron performs reliably in this circuit, 
requiring a minimum pulse of at least 150 volts from a source whose 
internal impedance is 1000 ohms or less. This thyratron proved to 
be capable of withstanding this intermittent heavy loading over long 
periods of time. 


The life of flashtubes can be considerably prolonged by limiting the 
duration of the flash burst so that the large amounts of power ex- 
pended in the tube do not cause blackening of its walls caused by 

Fig. 4 Flashtube circuit. 

sputtering of the electrode materials onto the walls. To restrict the 
total number of flashes for any one test run, the electronic equipment 
shown in Fig. 5 was introduced. The camera is started first and grad- 
ually increases its speed. During this interval the camera contactor is 
delivering signals to the pulse generator. However, the pulse genera- 
tor has been modified for use in this circuit so that it does not respond 
to these premature signals. This is accomplished by negatively bias- 
ing the output amplifier tube of the pulse generator well beyond the 
cutoff value. Thus no further action takes place during the accelera- 
tion period of the camera. A microswitch built into the camera is set 
to close after a predetermined number of feet of film has run through, 




thus providing an easily adjustable delay period during which the 
camera accelerates. The closing of this switch initiates the action to 
be photographed. At the same time, an interval timing switch is 
tripped and removes, for a preset interval, the negative bias on the 
output tube of the pulse generator. During this interval, the burst of 
flashes takes place. 


Tests were made of the photographic performance of the Eastman 
camera, both with flash and incandescent, lighting, by taking motion 
pictures simultaneously of moving and stationary resolving-power 
charts. The moving charts were mounted near the rim of a rapidly 
revolving disk. The three pictures on the left of Fig. 6 are enlarge- 


Fig. 5 Block diagram showing camera and multiflash 

ments of consecutive frames of a film taken with incandescent light- 
ing, while the other three were taken with flash lighting. Each pic- 
ture shows two sets of resolving-power grids numbered from one to 
ten; the set on the disk rotates at 1500 revolutions per minute with a 
peripheral speed of 78.6 feet per second, while the outer set is station- 
ary. The pictures were made at a camera distance of eight feet, with 
a Kodak Anastigmat, 102-mm, f/2.7 lens. Optimum exposure in 
each case had been determined by experience; the'lens was used at 
//6.5 for incandescent and at//5.6 for multiflash lighting. No changes 
were made in the focus of the camera, position of the camera, or posi- 
tion of the resolving-power grids between tests. Super-XX film was 
used and was developed as a negative in D-72 developer, diluted one 
to one. 

The numbers of lines per inch and per millimeter on the film were 
calculated for the various resolving-power grids and are listed in 




Table I. The films indicated resolving powers for the stationary grids 
of 1020 lines per inch (40 lines per millimeter) with flash lighting, and 
815 lines per inch (33 lines per millimeter) with incandescent light- 
ing. For the rotating disk, the resolving power with incandescent 
lighting was 356 lines per inch (14 lines per millimeter) while multi- 
flash lighting gave 815 lines per inch (33 lines per millimeter). Thus 




(A) Incandescent Lighting. 

(B) Multiflash Lighting. 

Fig. 6 Enlargements of resolving-power photographs with multiflash and 
incandescent lighting. In all the pictures the outer arc is stationary while 
the inner arc rotates at 1500 revolutions per minute. 

the resolving power was more than doubled by the use of multiflash 
lighting in this test. Obviously these results do not represent the ex- 
act limits of the resolving power in each case since the resolving-power 
grids represent only ten arbitrarily selected steps between 170 and 
1400 lines per inch or between 6 2 / 3 and 56 lines per millimeter. No 
intermediate determinations of resolving power were made between 
these steps. 


The resolving powers obtained seem quite reasonable when the lim- 
its imposed by exposure time and the resolving power of the film are 
considered. A resolving power of 1020 lines per inch (40 lines per 
millimeter) obtained with multiflash lighting and stationary grids is 
about that to be expected of Super-XX film with D-72 development. 
The lower resolving power which was found with stationary grids 
when incandescent lighting was employed can be attributed to blur- 
ring caused by the relative motion between the film and image during 
the longer exposure time. The multiflash-lighting data obtained with 
moving grids show a decrease in resolving power when compared to 
the stationary grids. This decrease is believed to be exaggerated by 




Grid Number Lines per Inch Lines per Millimeter 














612 * 
















6 2 /3 

the lack of intermediate readings between 815 and 1020 lines per inch 
(33 and 40 lines per millimeter) . With incandescent lighting and mov- 
ing grids, the resolving power dropped to 356 lines per inch (14 lines 
per millimeter) . This can be entirely accounted for by the motion of 
the object during the exposure time of approximately 110 microseconds. 


The authors wish to acknowledge the assistance given by Dr. 
J. H. McMillen, Dr. A. May, Mr. D. J. Milano, and other members of 
the Hydrodynamics Subdivision. 


(1) H. E. Edgerton, "Photographic use of electrical discharge flashtubes," J. 
Opt. Soc. Amer., vol. 36, p. 390; July, 1946. 

(2) F. E. Carlson and D. A. Pritchard, "Characteristics and applications of 
flashtubes," Ilium. Eng., vol. 42, p. 235; February, 1947. 



COMMANDER KENNETH SHAFTAN: Did you remove the prism with the East- 
man high-speed camera? 

MR. ROBERT A. ANDERSON: No. We timed our flash measurements to occur- 
when the shutter was in its wide-open position, that is, when the surface of the 
glass plate is perpendicular to the optical-center line. 

COMMANDER SHAFTAN: It seems to me that the resolution would increase tre- 
mendously by elimination of that quarter-inch glass plate through which you 

MR. ANDERSON: We intend to try using the camera with the prism in place at 
still higher speeds. In such pictures, the action of the prism might be of notice- 
able value in synchronizing the motion of the film and image during exposure time. 

COMMANDER SHAFTAN: The General Radio Company in Cambridge, 'Massa- 
chusetts, has a motion picture camera in conjunction with multiflash equipment. 
They get a resolution approximating about 70 lines per millimeter. I note that 
yours runs approximately 40 at its best with the multiflash system, and I think it 
is probably not due to image displacement but to the prism. Usually that prism 
does not promote very good resolution, particularly in your flash-duration period, 
in giving you an extending exposure, but also giving you a displacement of the 
image due to the rotation of the prism itself. 

MR. ANDERSON: I am not familiar with what type of film or development was 
used in the test with the General Radio camera. As I stated, our film was Super- 
XX and we used D-72 developer. 

Electronic Flashtube Illumination 
for Specialized Motion Picture 


Summary This paper presents a discussion of the possibilities of utilizing 
electronic flashtubes in synchronization with standard motion picture 
cameras at normal and moderately high exposure rates. The results of ex- 
perimental tests are described, and are followed by descriptions of two units, 
the Cine-Strobe-Light and the Universal Strobe-Light intended for use in this 
manner. Associated lighting equipment is shown, and results obtained, to- 
gether with side effects, are discussed. 

IN A PAPER presented before the Society of Motion Picture Engi- 
neers, 1 Carlson gave a preliminary appraisal of flashtubes from the 
point of view of motion picture studio photographers. He discussed 
the basic principles of repetitive flashing circuits, and the problems'in- 
volvedin the studio use of flashtube illumination, including the psycho- 
logical effect of a' flickering light source on the performer, and the elec- 
trical effects of large power discharges in proximity to sound-record- 
ing circuits. While no final conclusion could be drawn from these 
tests, the economic factors entering into them being unexplored, the 
paper did indicate that the results obtainable with conventional 
motion picture cameras established the possibility of such use in the 

It must be kept in mind that the flashtube was originally designed 
for motion picture photography, with shutterless high-speed cameras 
using a continuously moving film. Only later was it adapted to use 
with still cameras, and in this latter field gained wide acceptance by 
photographers in general. To some extent, the problem of using 
flashtubes with the conventional motion picture camera was a more 
involved one. No difficulty was anticipated in synchronizing .the 
light flashes with the camera shutter: this could easily be accom- 
plished with one of several conventional circuits. 

* Presented before the Rochester Section, Technical Division, Photographic 

Society of America, December 3, 1947. 



But the energy-storage principle used in most single-flash power 
packs gives a misleading impression of the power requirements of 
flashtube circuits. When 10 to 30 seconds are available to recharge a 
capacitor, power drain from the line is trifling. When the recharging 
must be accomplished in x /24 to l / M of a second, power requirements 
mount by leaps and bounds. 

A further problem is that of tube heating. Flashtubes are not 
designed to radiate much heat: in fact, this is one of the favorable 
factors which impelled their use in the examples to follow. On single 
flashes, the heat generated is dissipated completely in the interval 
between flashes. Repetitive flashing imposes a different requirement, 
and there was doubt that the conventional flashtube could stand up 
under such conditions. 

Experience with flashtubes used with the high-speed motion pic- 
ture camera was not of much assistance in this connection. Such 
tubes were specially designed for that service, and, in addition, a high- 
speed camera exposes its entire roll of film in a matter of seconds. 
With conventional motion picture cameras, continuous runs of as long 
as three minutes might be required. 

However, it appeared to the present writer that these difficulties 
were not insurmountable, and that the* electronic flashtube wouM 
provide an unusually valuable light source for certain specialized types 
of cinephotography. The high intensity of the light, its short dura- 
tion, and the low heat radiation were all advantages worth consider- 
ing against the aforementioned difficulties. 


It is not the function of this paper to explain more than the funda- 
mentals of flashtube power packs and the design of associated 
equipment. These, and the characteristics of flashtube illumination 
from the photographic point of view, have been covered at length by 
Murphy and Edgerton, 2 Carlson and Pritchard, 3 Edgerton, 4 and oth- 
ers. Basic circuits and components, and design factors for their use, 
have been. discussed by Edgerton, Germeshausen, and Grier, 5 and by 
Carroll. 6 

Basically, all electronic flash illuminators follow the elementary 
circuit shown in Fig. 1. The main capacitor is charged to a voltage 
somewhat below the self-discharging (or breakdown) point of the 
flashtube, by the main voltage source through the limiting resistor R. 
A similar circuit is used in the primary of the trigger transformer T t 

210 LESTER March 

which is designed to apply a pulse of approximately 15,000 volts to an 
external electrode on the flashtube. The application of this pulse 
ionizes the gas filling of the flashtube, lowering its resistance and 
causing the capacitor to discharge through the tube. This discharge, 
lasting from to of a second, results in the emission of a 
very intense flash of light. Because of the short time of the discharge, 
the instantaneous power values are very large, sometimes running as 
high as a million watts and more. This accounts for the very large 
light outputs resulting. 

The capacitor is charged through a 
limiting resistor R, previously men- 

2000 v DC =j= c, M FT tioned. This resistor serves two func- 

tions. First, it limits the charging 
current drawn by the capacitor at the 
beginning of each cycle to a safe value 
for the power supply. Second, it pre- 
vents the flashtube from drawing cur- 
rent directly from the pOAver source, 

. ele whicn would result in a COntinuOUS- 
glow discharge, damage to the tube, 
ahd overloading of the power supply. 

At extremely rapid repetition rates, the value of this charging re- 
sistor R necessarily must be small to permit substantially complete 
recharging of the main capacitor between flashes. Under the circum- 
stances, considerable danger of sustained-glow discharges (or "hold- 
over") exists. Deionization of the flashtube must then be accom- 
plished by other means, such as inductance added to the circuit to re- 
duce the voltage at the end of the flash to zero. Mercury switch-tubes 
such as the General Electric Capacitron are also used to aid in stopping 
the current flow at the end of a flash. The relation and action of these 
parts will be discussed at greater length in connection with the Cine- 

The present paper will discuss two special purpose power supplies 
for flashtube operation, and associated equipment for scientific mo- 
tion picture, photography. The first of these, the Cine-Strobe-Light, 
was designed for entomological photography on a macroscopic basis. 
It is strictly a single purpose unit, its design taking into account not 
only photographic problems, but also safety factors and the necessity 
for its use by untrained personnel. 

The second unit, the Universal Strobe-Light, is intended for use by 


the author's own staff: it is adaptable to a wide range of specialized 
photographic purposes, and was designed for rapid circuit changes and 
maximum versatility. This involved eliminating certain safety fac- 
tors which would have impeded immediate change of various circuit 
components. Other safety factors have been introduced in their 
stead, so that any part of the unit may be handled within a matter of 
seconds after power has been shut off. 

Fig. 2 Mockup of camera support, commutator (simu- 
lated by wiper operating microswitch) , and FT-429 flash- 
tube without reflector. 



The design and construction of the Cine-Strobe-Light was. the result 
of a request from a Western entomologist for a lighting unit which 
would permit macroscopic cinephotography of insects without exces- 
sive heat. Illumination levels had to be high enough to permit expo- 
sure on Kodachrome film, at frame frequencies from 16 to 64 exposures 
per second, and to permit use of lens apertures small enough for ade- 
quate depth of field at these close ranges. Because of the close 

212 LESTER March 

working distance, the light unit proper had to be very small; to 
avoid equipment shadows, it was required to work as close as possible 
to the lens axis. 

These requirements indicated that incandescent or arc illumination 
would not be practical, both on the ground of bulk and because of 
heat problems. While heat-absorbing cells and special glasses and 
filters are available, their use changes the color composition of the 
light to an undesirable degree. This unit was to be used by personnel 
who were not photographers; it was felt undesirable to present them 
with the problem of compensating the color of the light source by fil- 
ters or other means. 

The possibility of using flashtubes in connection with a cine camera 
had been under consideration for some time before this problem came 
up; it appeared to present the possibility of a solution in this case. 
Radiant heat from the flash appears to be favorably low, the flash it- 
self is intense, yet well diffused, and the color temperature of the light 
from a xenon-filled flashtube is almost exactly correct for use with 
daylight-type color films. 

Fortunately, there was available at the time, the General Electric 
Type FT-429 flashtube, a quartz ring 2 3 /4 inches in diameter. It 
appeared that such a tube, surrounding the lens, would provide ade- 
quate coverage of the fields to be photographed, and would have a 
very desirable shadowless quality. 

For a preliminary test, a simple wooden stand was made, and 
painted dead black. One of these tubes was mounted on the front, 
surrounding a hole in the board. A standard 16-mm motion picture 
camera was mounted to the base of this unit, with its lens pointed 
through the hole. (See Fig. 2.) A simple wiper was fastened to the 
crank shaft of the camera, in such position that it would operate 
a microswitch at the open point of the shutter at each exposure. 
(Fig. 3.) 

This setup was connected to a small power pack, similar to the port- 
able units sold for use with still cameras. Since this pack took sev- 
eral seconds to recharge, even with small capacitors, it was not pos- 
sible to run the camera at normal speeds ; however, a series of single- 
frame exposures was made to determine the power required for opti- 
mum exposure levels at the lens apertures to be used. 

The results of these tests indicated the possibility of securing ade- 
quate exposure under the required conditions, with between 12 and 14 
microfarads of capacitor working at between 1800 and 2000 volts. 




However, the problem of recharging a capacitor of that size in Ve4 of 
a second dictated the reduction of the final capacitance to 6 micro- 
farads, raising the circuit voltage to restore the power level to the 
same total amount.* 

However, another factor entered at this point, and made it unnec- 
essary to raise the .voltage all the way to the point of doubling the 
power output (this would have been 2800 volts). In preliminary 
tests, the front of the board on which the flashtube was mounted was 
painted flat black, so that only the actual illumination from the tube 
itself was being used. The addi- 
tion of a highly efficient reflector 
increased the light level at the 
subject plane to a degree which 
necessitated raising the voltage 
only to 2300 volts with 6 micro- 
farads, to secure the same light 
as 12 to 14 microfarads at 1800 to 
2000 volts without reflector. 

This reflector was designed by 
a member of our own staff as a 
parabolic toroid (or paraboloidal 
semitorus ... we have been 
unable to agree on just what the 
final shape is called). In effect it 
is a trough of parabolic cross sec- 

Fig. 3 Contactor built onto one- 
frame-per-turn shaft of camera, oper- 
ates microswitch to close trigger cir- 
cuit of flashtube. 

tion, bent into a circle to follow 

the tube. Mounting clips for the 

tube hold it quite accurately at 

the focus of the parabola. (See 

Fig. 4.) The reflector itself is spun from aluminum sheet and finished 

inside with matte Alzak; many favorable comments have been 

received on the unusually smooth light distribution and high effi- 

ciency of this unit. 

At this point, -all the basic design factors were known, except the 
important one. Would the FT-429 operate under such loading condi- 
tions? Basically, the FT-429 is intended for single flashes at widely 
spaced intervals, and is rated at 400 watt-seconds per flash. Our 

* Since the power (and light output) is given by the expression J = 

large increases in power can be obtained more easily by increasing voltage rather 

than capacitance. 




individual flash loading was far below this point: 6 microfarads 
at 2300 volts is actually not over 10 watt-seconds. 

But we were figuring on flashing at rates up to 64 frames per sec- 
ond; this is a continuous loading of 1024 watts, or more than 2 1 / 2 
times the rating of the tube. Even at 24 frames per second, the load 
was nearly 400 watts; while this was the design loading of the lamp, 
it was based on intermittent flashing with plenty of cooling time be- 
tween flashes. It was questionable whether the tube would stand up 
under such rigorous treatment. 

Even if it would do so, there 
was another unknown : how long 
would it last? Little is known of 
the actual life of flashtubes: they 
are nominally rated at 10,000 
flashes. - At 64 frames per second, 
this would give a $28.00 tube a 
total life of 3 minutes, and even 
at 24 frames per second, hardly 
more than 7 minutes. 

At this point, the problem 
was moved to Boston. Dr. 
Edgerton and Mr. Wyckoff, of 
the Massachusetts Institute of 
Technology, assembled a bread- 
board mockup of the power 
supply, with a motor-driven 
commutator simulating the -cam- 
era. A single FT-429 was oper- 
ated at the desired loading, and at 24 flashes per second, in 3-minute 
bursts, simulating 100-foot rolls of 16-mm film. At the end of five 
such bursts, the tube was still operative, though its electrodes had 
practically evaporated, and the tube was blackened to a degree se- 
verely limiting its light output. 

The tube electrodes had reached white heat at the end of each burst, 
and the tube itself was far too hot to touch. Nonetheless, the radiant 
heat at a distance of a few inches was negligible. It was thought, 
therefore, that if such tube life could be obtained under the most un- 
favorable conditions, even greater life could be expected if the bursts 
were held to a few seconds each, the normal procedure for motion pic- 
ture photography . Later this was borne out in practice. 

Fig. 4 Toroidal-parabolic reflector 
with FT-429 tube flashing. Note even 
reflection and light distribution. 




The test, furthermore, indicated the practicality of the circuit and 
of the use of this particular tube. It was thought advisable at this 
point, to proceed with the construction of the final form of the power 

Final Form 

The workability of the plan having been demonstrated, Dr. Edger- 
ton and associates were requested to build the final model of the 
Cine-Strobe-Light power pack, using the circuit constants already 
mentioned, namely, 6 microfarads at 2300 volts. In addition, all pos- 

T2 , w k 

Fig. 5 Schematic circuit of the Cine-Strobe-Light. 

sible safety factors were to be included in the circuit. Our own shop, 
meanwhile, designed and constructed the necessary lamp housing, 
reflectors, camera commutators, and other accessory equipment. 

As can be seen from Fig. 5, the basic power-supply circuit has been 
modified by the addition of a number of associated elements; some of 
these are for safety reasons, others are because of the high-power load- 
ing and flashing frequency. 

Thus, for example, the simple switch circuit for triggering the flash 
has been replaced by a triggertube Type OA5; this tube acts like a 
relay, but being electronic in action, has no time lag. Since it oper- 
ates by variation of the voltage applied to its grid, the current carried 
by the camera contacts is negligible, and no danger exists, either to 
the camera operator or to the contact points. 




Similarly, plate (or high-voltage) and filament circuits are fed 
from separate power transformers. In this way, all. filaments can be 
preheated before use, and the pack can remain in operative condition 
between shots, with no high-voltage present until actually needed. 

The high voltage is fed to the flashtube through a Capacitron which 
acts as a switch. In this way, even with the high-voltage transformer 
energized, there is no high voltage present in the tube wiring or termi- 
nals except while the tube actually is flashing. In addition to this 
switching function, the Capacitron also serves to aid in deionizing the 

Fig. 6 Front of Cine-Strobe-Light power pack, showing switches, 
plugs, and pilot lights. All are marked to correspond with the cir- 
cuit diagram; all are different in size and shape to prevent any possi- 
bility of misconnections. 

flashtube and prevents holdovers or glow discharges. This is ac- 
complished in connection with the third rectifier tube and an induct- 
ance, in a manner which will be explained later. 

As can be seen from the circuit diagram, there are a number of ex- 
ternal connections to be made. These are done with plugs, all of 
which differ from each other both in number and spacing of prongs, 
so that it is impossible to put any plug in the wrong socket, or to in- 
sert it in the correct socket the wrong way. (See Figs. 6 and 7.) 

A compact, well-insulated commutator was designed and built to 
fit the single-frame crank shaft of the camera. (Not shown here.) 
It was essential that this place the minimum drag on the shaft as the 




gearing at this point is high in ratio to the rest of the camera and a 
small load on this shaft will slow down the camera seriously. Since 
little current is carried by the commutator points, they were made 
small in area for minimum frictional effect, a spherical tip being used 
on the brush, and the commutator contact itself being a bar of bronze, 
flush with the surface of the commutator rotor. The commutator 
connects with plug P 2 on the 
power pack: this outlet, of 
course, could also be used for 
a still-camera shutter or a free- 
running commutator for multi- 
exposure (or stroboscopic) uses. 

PI is the main input plug for 
the 115-volt, alternating-current 
line. It is connected to the main 
switch Si with thermostatic over- 
load trip FI. The filament and 
trigger circuits are separately 
fused F and the yellow-green 
pilot light LI indicates when 
these circuits are in operation. 

Power from the main switch 
also goes to the high- voltage 
circuit, through a relay S 3 , which 
is operated by means of an ex- 
ternal switch plugged into P B . 
The relay coil is energized 
through $ 2 which is a safety 

Fig. 7 Top view of Cine-Strobe- 
Light power pack, showing control 
circuit, including 5R4GY rectifier in 
foreground and OA5 triggertube (the 
small tube directly behind it). Three 
filter capacitors in foreground; main 
flash capacitor in the rear, under the 
reactance (or choke) in the Capacitron 
circuit. Capacitron tube partly visi- 
ble behind the control chassis. 

switch, so placed that it is auto- 
matically opened if any of the 
covers or panels of the power 
pack are removed. Thus no 
high-voltage circuit can be energized unless the pack is completely en- 
closed and all covers in place. A red pilot light L 2 indicates that the 
high-voltage circuit is energized. 
From the safety standpoint, therefore, triple protection is afforded: 

1. High voltage cannot be turned on unless all covers and panels 
are in place. 

2. The switch carries only the relay-coil current, and must be held 

218 LESTER March 

3. A red warning light glows whenever high-voltage circuits are in 

In addition, because of the use of the Capacitron tube, there will 
still he no high-voltage present at the lamp terminals until the cam- 
era contacts close, and then only during the actual flash of the lamp. 
Separation of the high-voltage and the filament circuits also permits 
preheating of the rectifier tubes before plate voltage is applied. This 
is important, since mercury-vapor rectifier tubes are used, and the 
mercury must be vaporized fully before operation. 

The primary of the high-voltage transformer is fed through a vari- 
able autotransformer, providing adjustment for line-voltage condi- 
tions and also making it possible to increase the secondary voltage if 
additional light output is required. The output of this power trans- 
former is rectified by two 866- A mercury- vapor rectifiers in a full-wave 
circuit. These tubes were chosen because of their large power-han- 
ling capacity and low internal voltage drop : the loss in the tube is 15 
volts regardless of load. 

To provide good voltage regulation, reduce line surges, and de- 
crease the load on the rectifier circuit and power transformer, the 
direct-current output is filtered by choke T 6 and capacitor Ci of 84 
microfarads. This filter provides the greater part of the charging 
supply of the heavy current demand at the beginning of each charg- 
ing cycle immediately after a flash takes place. 

For safety reasons, this filter is bridged by resistors totaling 100,000 
ohms which bleed off the charge when the power is shut off. The out- 
put of the filter is fed through choke Tj to the main flash capacitor C 2 
which as previously mentioned, is 6 microfarads. This also has a pro- 
tective bleeder of 4.5 megohms, which will drain it to a safe level in 
about 30 seconds, after power is removed. 

Power from the capacitor C 2 is fed to the flashtube through the Ca- 
pacitron or mercury switch tube and choke 7 7 9 which act to drop the 
voltage to zero at the end of each flash. Since the circuit contains both 
inductance and capacitance, any tendency it may have to develop os- 
cillations is damped out by the third mercury-vapor rectifier tube Vi c , 
another 866-A, which prevents reversal of the current flow. 

The trigger circuit is completely separate from the power circuit; 
it has its own power transformer T 5 and its own rectifier Vz f this 
latter being a high-vacuum type 5R4GY connected as a half-wave 
rectifier. Its output is smoothed by filter capacitor (7 3 , and charges 
capacitor C 5 to approximately 800 volts. 


V 3 is the triggertube, type OA5, which serves as a switch to dis- 
charge C 5 through the primary of the trigger coil TV It is operated 
by the camera commutator, which merely shorts out grid resistor R&. 
A network of resistors R, R$, and RT, and capacitor C* is placed in the 
grid circuit to assure that each contact of the commutator results in 
only a single pulse being applied to the grid of the tube, avoiding the 
possibility of double tripping. 

Resistors R* and R 9 apply voltage to the "keep-alive" grid of the 
triggertube. This grid maintains a small amount of ionization in the 
tube at all times and stabilizes its tripping time. 

The triggertube acts in the same manner as a simple switch, dis- 
charging capacitor C 5 through the primary of the trigger coil TV This 
coil, or transformer, applies a 15,000-volt charge to an external elec- 
trode or band placed around the neck of the Capacitron. Since the 
Capacitron and the flashtube are effectively in series, the ionizing volt- 
age acts on both simultaneously, and the flash takes place. 

The cable connecting the flashtube to the pack is a coaxial type with 
polyethylene insulation : it carries both flashing power and the trigger 
pulse. For this reason, an optimum length and diameter exist for this 
cable. If the cable is too long or too small in diameter, it will have ex- 
cessive distributed capacitance, which will tend to damp out the trig- 
ger pulse and make flashing erratic. With a cable of correct dimen- 
sions, resistor R 3 aids in neutralizing this effect by putting a small 
charge on the cable. 

The flashtube and reflector are mounted on a metal box which 
serves as terminal housing, avoiding exposed high-voltage connec- 
tions. Both box and reflector are grounded for additional protection. 


With the constants given, the unit has an exposure-guide number 
of 100 (in inches) for Kodachrome Daylight Type with CC-15 filter, 
and 300 (in inches) for black-and-white reversal film having a Weston 
rating of 100 to daylight. Thus at 9 inches from the subject, the ex- 
posure will be//ll for color film and //33 for black and white. (See 
Fig. 8.) 

The exposure time is about 1 /2o,ooo of a second; therefore, it should 
appear that film exposure should be substantially independent of 
camera speed. This would be true, but for the fact that at higher 
frame frequencies, the capacitor does not recharge quite completely. 
Hence it has been found necessary to increase the exposure somewhat 




at higher camera speeds. The effect is far less than with normal 
lighting, however, being about one half stop extra at the maximum 
speed of the camera (64 frames per second). 

The power demand of the unit varies, of course, with the flashing 
rate; it has a total current drain of about 23 amperes at 115 volts 
when running at the maximum rate of 64 frames per second. The 
power drain is roughly in proportion to the camera speed at other 
settings, but a fixed amount of current is used for filament and control 


80 US 90 95 100 105 110 115 120 


Fig. 8 With the Cine-Strobe-Light, having limited voltage variation, the 
graph gives exposure-guide numbers in inches for varying primary voltages. 
Capacitance being fixed, only one curve is needed for each film type, and this 
unit was to be used exclusively with Kodachrome film, daylight type. 

circuits so that the total drain does not drop as rapidly as expected 
(See Fig. 9.) 

Incidental effects are few, but in some cases, significant. Some 
ozone is generated by the discharge around the flashtube and the 
Capacitron. The quantity is negligible, and no precautions need be 

* EDITOR'S NOTE: Ozone is considered to be very toxic in rather small concen- 
trations. See Henderson and Haggard, "Noxious Gasses," American Chemical 
Society monograph, 1927. (No effect has been noted from the small amounts 
emitted by equipment of this type.) 




A more important effect is the large quantity of ultraviolet radiation 
emitted by the flashtube. Since the FT-429 is of quartz construction, 
the ultraviolet output is much higher than that of ordinary flashtubes, 
and far greater than that emitted by incandescent or arc sources. 
This does not seem to bother the insects being photographed (accord- 
ing to authorities of the American Museum of Natural History, some 
flies are actually attracted by ultraviolet) . 

From the operator's standpoint, a good pair of high-quality sun- 
glasses, such as Bausch and Lomb "Ray-Ban" or American Optical 
Company "Calobar" appears to afford adequate protection. 

90 95 100 105 110 115 120 125 


Fig. 9 

Motion pictures taken with this unit show the expected strobo- 
scopic effects on subjects in repetitive motion, such as wheels or drip- 
ping water. Slow, random motions appear on the screen with quite 
satisfactory smoothness of motion; rapid random motions appear er- 
ratic. The individual frames, as might be expected, show no motion 
blur whatever, and may be of especial benefit when individual frame 
enlargements are desired for study. 

The expected flatness of illumination resulting from a light source 
surrounding the lens did not materialize. A remarkable degree of 
modeling actually is obtained, probably because of the closeness of the 

222 LESTER March 

source, which results in large inverse-square-law effects at short dis- 
tances. Some of the excellent quality obtained may also be- due to 
the property which strobe light seems to have, of retaining high-light 
detail, even in fully exposed areas. Nonetheless, the light is shadow- 
less in the best sense of the word. 

Electrically, the unit operated as expected. Only one unusual ef- 
fect was found. In a conventional flashtube, the terminal support- 
ing the barium "getter" pellet is usually considered the negative 
or cathode end of the tube. However, it appeared that some (but not 
all) tubes would operate with the polarity reversed. The only un- 
toward result of reversed polarity appeared to be more rapid black- 
ening of the tube. 

After the pack was constructed and undergoing tests, the General 
Electric Company was induced to make several minor changes in the 
FT-429 flashtube which was still in an experimental stage so far as 
they were concerned. In collaboration with one camera manufacturer 
who plans to use this tube in a future product, agreement was reached 
on a wider and "squarer" spacing of the external connections, and 
larger internal electrodes. The former increases the safety factor, es- 
pecially in damp weather, and permits the design of a better terminal 
box. The latter change seems to make flashing more reliable, and 
definitely adds to the life of the tube. 


The Cine-Strobe-Light was tested over a long period before de- 
livery to the client. (See Fig. 10.) Its use indicated a number of pos- 
sibilities in other fields of photography, provided the design were 
modified to allow greater flexibility. The design points chosen were 
as follows : 

1. It should be possible to change capacitors very rapidly so that 
optimum power could be used for any purpose. 

2. Variable voltage was desirable for finer control of light output, 
exposure, and charging time. 

3. The triggering unit should be independent of the power pack, so 
that it could be used with still or motion picture cameras, or operated 
independently as a stroboscopic illuminator. 

4. It should be usable with a variety of flashtubes, for special 
lighting problems. 

5. Since the unit would be operated only by skilled personnel, some 
of the more elementary safety features, such as screwed-on panels 




and door switches, should be omitted because of the necessity for mak- 
ing frequent circuit changes. However, to facilitate the making of 
such changes in safety, bleeder relays must be supplied to drain all 
voltage off the capacitors within a few seconds of cutting off the power. 
In the light of these considerations, it was decided that the power 
pack would contain only transformers, rectifiers, and control compo- 
nents. All capacitors are external and plug in through a high-volt- 
age coaxial connection. Triggering is also external and connects 

Fig. 10 Universal Strobe-Light. Capacitor bank lower left. Variac con- 
trolling primary voltage to power pack, top left. Main power pack with FT- 
429 flashtube assembly and Strobotac, top right. Weston Model 779 volt- 
meter and televerter used as kilo volt meter for measuring terminal voltage, 
lower right. 

through a plug into the lamp circuit. All connections are made to 
plugs on the face of the power pack ; thus it also serves as a central 
terminal box and switchboard. 

The power pack, therefore, was wired according to the schematic 
diagram (Fig. 11). 7\ is a General Radio Corporation Variac provid- 
ing control of -the input voltage to the high-voltage transformer. 
This latter is rated at 4000 volts output from an input line of 117 
volts. T 3 is the filament-heating transformer and is separately con- 
nected so that all filaments secure their correct voltage and current 
regardless of the voltage input to the power transformer. The use of 




separate transformers also permits preheating of the mercury-vapor 
rectifier tubes, Type 866-A, as in the Cine-Strobe-Light. 

No filtering is used in this pack ; instead a charging resistor RI was 
chosen to permit sufficiently rapid charging up to 64 frames per sec- 
ond with not over 6 microfarads of capacitor. Larger capacitors can 
be charged at a slower rate. The capacitance of the unit is sufficient to 
charge 135 microfarads at rates approaching 1 flash per second. 

However, in this extreme case, charging of the capacitor is not com- 
plete : this is compensated by the Variac in the primary of the power 
transformer. If the time constant of the capacitor-resistor combina- 
tion in use indicates that only 80 per cent of full charge can be reached 

Fig. 11 Schematic circuit of the Universal Strobe-Light. 

in the time given, and 2000 volts is required at the flashtube, then the 
secondary voltage of the transformer is set to 2500 volts and the capac- 
itor will just be reaching the 2000-volt level as the flash takes place. 

Pin jacks are provided in parallel with the capacitor plug for the 
insertion of plugs connecting to a Weston Model 779 voltmeter and 
Televerter. This meter and attachment have a combined range of to 
5000 volts at 20,000 ohms per volt; on the 5000-volt scale the resist- 
ance in the circuit is 100 megohms and the drain on the capacitors is 
negligible (about Vso of a milliampere) . The meter, when plugged in, 
indicates the actual voltage being delivered to the flashtube, rather 
than the charging voltage from the transformer. Since the light out- 
put is proportional to the square of the voltage, errors in voltage are 


more serious, exposurewise, than changes in capacitance, and the use 
of a voltmeter is insurance of correct exposure. 

No Capacitron is used in this unit, and the trigger transformer is 
mounted directly to the flashtube housing. In this way the leads car- 
rying the 15,000-volt pulse are kept down to a few inches in length and 
the capacitance of the cable is of minor importance. A twin coaxial 
cable is used, the central wire carrying the flashing voltage; the 
inner shield carries the primary pulse to the trigger coil and the 
outer shield is grounded and acts as common return for both circuits. 

The trigger plug accepts any type of switching device provided it 
supplies its own pulse current. A simple trigger circuit similar to Fig. 
12, might be used. However, such a unit could only be used where the 
switch contacts can carry considerable current, and there is always 
danger of double tripping. 

For this reason a trigger circuit such as that in the Cine-Strobe-Light 
would be preferable. A ready-made triggering unit was found in the 
General Radio Corporation 
"Strobotac". This instrument R ? 

contains all the elements of the 
previously shown triggertube 

circuit, and has its own* self- Fig 12 _ C ircuit for triggering flash- 
contained power supply. In ad- tubes, 
dition, it also contains timing' 

circuits so that it can be set to flash at any desired frequency from 
1 flash per second up to 240 flashes per second. The internal tim- 
ing circuit may be disconnected and an external switch contactor, such 
as the camera commutator used with the Cine-Strobe-Light, may be 
used to operate the Strobotac. 

The Strobotac uses the Sylvania 1D21 tube both as a light source 
and triggertube. Its output is quite sufficient. to operate the trigger 
transformer at its optimum level, for a 15,000-volt output pulse. 

The internal timing circuit of the Strobotac is instantly adjustable 
by means of a calibrated dial to any desired speed of flashing; thus it 
can be used in connection with a still camera for multiple-exposure 
stroboscopic photography. With cine cameras it may, as mentioned, 
be operated by a commutator. Or it may simply be used as a trigger 
circuit for single flashing with a still camera. 
Exposure Determination 

The Universal Strobe-Light was designed, as mentioned, to be used 
with a variety of flasthubes, a few of which are described below. In 

226 LESTER March 

addition, the unit has a fully variable power output, attained by con- 
trol of voltage and choice of capacitance. Under the circumstances, 
determination of the required exposure, if done in the manner already 
explained in connection with the Cine-Strobe-Light, would require 
several volumes of graphs. 

A mathematical solution to the problem appeared preferable to a 
graphical one. Edgerton 4 has pointed out that the light output of a 
flashtube is a function of the applied voltage, the capacitance, and the 
tube efficiency (which is conditioned by the gas-filling pressure and 
other manufacturing factors). 

Photographers using flash illumination are accustomed to using a 
flash-guide number for determining exposure. This number is the 
product of the /-stop and the lamp-to-subject distance. Thus if one 
factor, such as the distance is known, the /-stop is found by dividing 
the flash-guide number by the distance. 

Edgerton 4 has shown that the flash-guide number (Df) can be cal- 
culated for flashtubes by the following formula : 

where Df = the guide number 

K = film speed/development constant 
n = efficiency of flashtube in lumens per watt 
C = capacitance in microfarads 
E = voltage in kilovolts 
M = efficiency of reflector 

This formula, then, contains all the necessary factors for determi- 
nation of an exposure-guide number. The only factor which must be 
determined empirically is the film-speed/development factor K; 
reference should be made to the original paper 4 for the method. A 
table of K factors for most popular films is given in that paper, as well. 

The determination of flash-guide numbers with the above formula, 
while simple, is somewhat tedious, and certain simplifying assump- 
tions can be made. For example, most flashtubes have an efficiency 
in the vicinity of 35 lumens per watt ; this figure can then be consid- 
ered a constant. Similarly, the average well-made reflector increases 
the light intensity in the center of the field by a factor of 10 over the 
bare-bulb value. 

Making these two assumptions reduces the formula to the form 

Df = K Vl75C 2 
where Df is the required guide number, D being in feet. For low power 


loadings and close-up photography, the factor 12 may be included: 

Df = 12K Vl75C 2 

in which case D is measured in inches. 

The value of K for a few typical cases is as follows : 

Super-XX for thin negatives 0.7 

Super-XX for fully exposed negatives . 35 

Kodachrome, daylight type (35-mm and Bantam)* 0. 11 

Kodachrome, professional film, daylight type* , 0.076 

Ektachrome, daylight type** 0.076 

* With Eastman Color Compensating Filter, CC15. 
** With Eastman Color Compensating Filter, CC33. 

By the use of the formula, with capacitance known, and voltage 
read on the meter mentioned, an exposure-guide number can be cal- 
culated for any desired setup. In many cases, no tests at all are re- 
quired; the*few remaining require only slight modification of the Df 
f actor 4 after tests have been made. 

Flashtube Mountings for the Universal Strobe-Light 

The principal feature of the Universal Strobe-Light being its flexibil- 
ity, it is necessarily designed for use with a wide variety of flashtubes. 
Some of those used with this unit are the FT-503, 403, 429, 220, 214, 
210 as well as some experimental types. Special mountings have been 
built for each type of tube for use with associated equipment: (See 
Fig. 13.) 

A variety of flashtube mountings has been built for use with the 
Universal Strobe-Light. One is a ring tube, FT-429 with housing and 
reflector, as supplied with the Cine-Strobe-Light. This is designed for 
close-up work with both cine and still cameras. A second unit con- m 
sists of a simple housing containing an FT-220 flashtube with integral 
sealed-beam reflector. For still greater light output, an FT-403 or 
FT-503 is used. These last two tubes have provisions for inserting a 
small incandescent lamp through a hole in the base, so that light ef- 
fects can be studied before flashing. 

The most specialized light unit so far built consists of a ring tube FT- 
429 within a reflector. This unit was designed for low-power photo- 
micrography of opaque objects. The FT-429 delivers adequate il- 
lumination for color photomicrography on Kodachrome or Ekta- 
chrome film, daylight type. This unit was of special value in the pho- 
tography of certain chemical crystals which had so low a melting point 




as to be completely ruined by heat from conventional micro- 
scope light sources. (See Figs. 14 and 15.) 

Flashtube illumination has proved to be of great value in time- 
lapse cinephotography. One such setup included the FT-429 ring 
tube, a specially designed camera motor designed to make one revolu- 
tion and stop each time a relay was energized, and also operating a 

Fig. 13 Universal Strobe-Light power pack with some of the flashtubes 
it operates. Left to right: FT-429, FT-220 (sealed beam), FT-503 
(similar to FT-403, but with quartz helix preferred for multiple flashing) , 
FT-214. Though these lamps vary in shape, size, and possible applica- 
tion, their light output is based on the same formula : 

Df = K 

microswitch at the shutter-open point of the camera cycle. The cam- 
era motor was controlled by a Kodak interval timer, and its contac- 
tor, in turn, operated the Strobotac, which flashed the tube. 

The same setup has been used with flashtubes such as the FT-403 
and as much as 135 microfarads of capacitance. The unit was per- 
mitted to run unattended for a period of 6 days/ to make a picture of 
the growth and decay of a rosebud. Because of the short duration 
and absence of heat from the separate flashes (at 2-minute intervals) 
the entire sequence was photographed in a darkened room. This 




avoided the movements and variation in growth of a flower subjected 
to alternate periods of daylight and darkness. 

Other time-lapse sequences required variations in time from 1 ex- 
posure per second to 1 exposure every 5 minutes. A short prelimi- 
nary run with the voltmeter connected was all that was needed to set 
the capacitor voltage at the desired point for correct exposure. 

Fig. 14 A specially designed housing supporting the FT-429 
flashtube with trigger coil in separate box, as used on a photo- 
micrographic outfit for low-power photomicrography of sub- 
jects sensitive to radiated heat. A similar setup is currently 
used for cinephotomicrography of living organisms. 


It would appear that electronic flashtubes hold a great deal of prom- 
ise as light sources for motion picture photography. Particularly in 
scientific and research photography, where a cool, highly intense 
light source of great uniformity is required for the photography of 
limited areas, the flashtube appears to be the immediate solution of 
the problem. 

230 LESTER . March 

On the other hand, it is apparent from the size and bulk as well as 
the power drain of the units shown here, which were designed for 
small area coverage only, that units for studio motion picture photog- 
raphy may have only limited application. In addition, the flicker of 
the light, and its high ultraviolet output, appear to restrict the possi- 
bility of its use with actors. 

Fig. 15 An electric-motor drive for intermittent operation of motion 
picture camera employed in time-lapse photography. Operating at fre- 
quencies starting at one frame per second, it can be employed for any 
other frequencies in conjunction with a proper timer. Each revolution 
of the camera shaft operates a microswitch at the open-shutter point of 
the camera cycle. This, in turn, triggers the flashtube. 

The Cine-Strobe-Light, for example, weighed over 350 pounds, 
drew 2 l /2 kilowatts, and had a light output just sufficient for an area 
measured in inches. 

On the other hand, the flicker problem is a psychological one only. 
The uniformity of exposure on the film was far beyond the expected; 
this applies equally to normal speed cinephotography with a camera 
running 24 frames per second or faster, and to time-lapse work, with 
'an appreciable interval between exposures. In some cases, especially 


that of time-lapse photography, the evenness of exposure actually ap- 
pears better than similar pictures taken with incandescent light : this 
would appear to be due to the fact that minor variations in camera 
speed, or loose shutter gears can have no effect on the exposure. Some 
motion flicker (or discontinuity) does occur with rapidly moving sub- 
jects, but this has no relation to exposure, and exposure flicker is to- 
tally absent. 

Two units designed for cinephotography in research have been 
presented in this paper; it is expected that they will be the fore- 
runners of others as photographers and research workers ap- 
preciate the advantages of flashtube illumination. The Universal 
Strobe-Light, as shown here, is still to be considered an experimental 
unit, for exploratory purposes. Preliminary results obtained through 
its use indicate, at least, the direction in which the design of a univer- 
sally useful, professional electronic flashtube power pack should tend. 

Certainly, the application of a voltmeter to such a power unit, 
and the calculation of exposure-guide numbers from its readings and 
the capacitance in the circuit, could be carried to a logical conclusion. 
It is expected that future versions of such equipment could include 
built-in meters, calibrated directly in exposure factors or guide 

This would be possible in most cases, only in a unit containing 
internally all of the elements now used in accessory form. Thus a 
Universal Strobe-Light should have: 

1. Voltage flexibility: Attained by a built-in variable voltage 
transformer, and controlled with a built-in voltmeter. 

2. Flexible capacitance values: When and if switches are avail- 
able which can handle the enormous surge of current at the high volt- 
ages used, all capacitors might be internal, and switched in or out in 
even increments. 

3. Variable charging rate: The use of a number of different 
charging resistors through switches, to attain an optimum charging 
rate for any desired capacitance, to avoid excessive line drain. 

With these factors all controllable from the panel of the unit, 
calibration charts reading directly in flash-guide numbers would make 
the use of the system no more complicated than the handling of 
ordinary flashlamps in the studio. 

Again, it must be emphasized, these are possibilities only. To the 
author, they appear both practicable and possible. Other photog- 
raphers may prefer a different solution to their particular problems. 


The element of importance, it seems, is that the basic flexibility of 
electronic flashtube illumination, provides scope for as many in- 
dividual methods of working as there are photographers using the 


To Harold E. Edgerton and Charles Wyckoff, for design of elec- 
trical circuits and construction of power units, as well as advice, 
encouragement, and assistance. To Earl Lee Auld and F. E. Carl- 
son, of the General Electric Company, for assistance in securing the 
necessary components, and for initiating with the Company, modi- 
fications in the design, of the FT-429 flashtube for better operation 
and easier handling in the Cine-Strobe-Light. To John S. Carroll 
for assistance in the design and construction of these lighting units. 


(1) F. E. Carlson, "Flashtubes: A potential illuminant for motion picture 
photography," /. Soc. Mot. Pic. Eng., vol. 48, p. 395; May, 1947. 

(2) P. M. Murphy and H. E. Edgerton, "Electrical characteristics of strobo- 
scopic flash lamps," /. Appl. Phys., vol. 12, p. 848; December, 1941. 

(3) F. E. Carlson and D. A. Prit chard, "The characteristics and applications of 
flashtubes," Ilium. Eng., vol. 42; February, 1947. 

(4) H. E. Edgerton, "Photographic use of electrical discharge flashtubes," /. 
Opt. Soc. Amer., vol. 36, p. 390; July, 1946. 

(5) H. E. Edgerton, K. J. Germeshausen, and H. E. Grier, "Multiflash photog- 
raphy," Photo Technique, vol. 1, p. 14; October, 1939. 

(6) J. S. Carroll, "Principles and design factors of electronic flash units," Elec. 
Manufacturing, vol. 39, p. 47; April, 1947. 

Synthetic Sound on Film* 






Summary An analysis of both hand-drawn and machine-made sound 
tracks is presented together with methods. 

Of fundamental importance is thp fact that synthetic sound tracks for the 
first time enable a composer to hear his composition as written rather than 
through artists' interpretation. 

Three basic methods are presented: (1) hand drawing directly on the 
film, (2) frame-by-frame photography of drawings and patterns, and (3) 
mechanical generation by machines, such as the harmonic integraph, which 
are coupled to a variable-area or -density modulator registering on the film. 


THE SUBJECT of synthetic sound on film is indeed an interesting 
one, so much so that it is not difficult to start a lively conversa- 
tion on the subject. Perhaps this condition is due more to the 
elementary nature of present-day thought on synthetic sound than 
anything else in particular, or perhaps it is the attraction of a new 
musical instrument. But whatever the attraction, the present stages 
of development are so vague and crude that many improvements 
on the processes herein described are readily conceivable. A dis- 
cussion of the subject therefore becomes more a statement of the 
present stage of general development than a discussion of a small 
increment of improvement on a particular aspect of the problem. 

In presenting the possibilities of synthetic sound on film as well as 
a few simple accomplishments, it is hoped that a basis for further 
development will be established. The present state of the art appar- 
ently is such that the production of a sound track to any particular 
score is only remotely possible. This is due largely to the fantastic 
labor required in the animation of sound and the difficulties entailed 
by transients, attack and decay, and similar problems. 

* Presented October 21, 1947, at the SMPE Convention in New York. 




In a survey of the limits of motion picture literary and esthetic 
possibilities, one finds the usual efforts diverging into further develop- 
ment of the traditional problems of mechanics, light, and sound repro- 
duction. An effort to develop new areas in a literary way seems 
promised by the use of animated sound; roughly, it is to the sound 
track what animation is to picture reproduction. 

The animated or generated sound-on-film of synthetic sound might 
well be defined as the placing on photosensitive film of images which 
produce systematic sounds by reproduction in the accepted motion 
picture manner, this new type sound being not necessarily a repro- 
duction of known sounds or previously recorded sounds or related 
phenomenon. The simplest means of sound animation is that of 
drawing the sound directly on the film. Another process to produce 
this type sound is the frame-by-frame exposure of drawings of sound 
waves, changed, arranged, and drawn in such a manner as to control 
tonal quality, pitch, and amplitude. 

The production of synthetic sound on film is to be differentiated 
from the " Voder" process of Bell Laboratories, as demonstrated at 
prewar World Fairs, in that the film process has, in effect, a "memory" 
and does not of necessity require manufacture of the sound at 'the 
same rate as that of the reproduction and, therefore, allows time for 
more complex processes and arrangements. The chief advantage in 
this use for film is the opportunity afforded for continuous playback ; 
the disadvantage, the lack of completely instantaneous playback. 

The synthetic sound on film is to be differentiated from the Ham- 
mond Organ, Novachord, and the radio-piano, in much the same way 
as the " Voder". The film process is also capable of recording non- 
continuous and nonuniform tones and notes such as occur in per- 
cussion. Also, it is capable of producing various types of tone- 
quality shift of a continuous nature through the playing of the note, 
as is exhibited in the solo Theremin. The film process is not neces- 
sarily dependent on the dexterity of a player artist and, therefore, 
allows more thought and choice to be exercised for each passing 
second. Obviously, the film process due to its memory and amount 
of time available in "recording" is not limited to one keyboard but 
may handle all types of sound. 

Immediately the question of the relation of synthetic sound on 
film to magnetic recording raises the question of the literary end or 
purpose. The immediate playback allowable via magnetic recording 


is an advantage, though not a complete one, as tones and rough 
combinations of tones may be played back immediately prior to 
chemical development or processing by a refinement of some other 
synthetic sound-recording systems. Duplication and re-recording 
in synchronism of separate magnetic recordings with picture do not 
allow repair of broken picture film and appear clumsy in this relation, 
necessitating the use of direct magnetic sound on film. It seems in 
order to point out the existence of the problem of recording magneti- 
cally with the material running at less than playback speed, as re- 
quired for synthetic-sound systems. 

It is obvious, that with adequate development of the technique 
required, standard musical score and human voices may be syn- 
thesized on film by the aforementioned processes. Also, it is obvious 
that percussion instruments, various new instrument effects, and 
unnatural speech -can be produced all too easily. As a tool of the 
composer it enables him to fix, in his mind as well as on film, and 
arrange his composition with a completeness as to tone, timing, and 
amplitude better than is possible with existing musical notation, 
without the economic cost of the reproducing musicians and their 
varying interpretations. It is probable that at the present, no other 
method approaches the theoretical possibilities of this method as a 
tool for a composer. 

Production of sound films -by this synthetic process should also 
allow experimentation and research into the nature of sound relations. 
Also by this process, test films might well be synthesized avoiding 
conventional recording errors, though, of course, introducing troubles 
of another nature. 

Without much imagination it can be seen that an offshoot of the 
basic process should allow the production of better matched and cued 
fades and mixes. This should allow greater liberty in editing. In 
all probability, as in the case of picture animation, it will be some 
time before synthetic sound develops any worth-while literary and 
esthetic qualities further advanced than this type of engineering 
discussion. Nevertheless, for the enjoyment in itself, the authors 
have found experiments and discussions concerning synthetic sound 
an adequate enjoyment to justify the effort. 


. A variable-area sound track readily suggests its duplication and 
modification by hand for one or a dozen reasons. A simple scribble 


in the sound-track area will make a noise, the challenge being the 
production of controlled tones of a pleasant nature. 

In order to produce such a sound film without resorting to costly 
equipment, it is necessary to resort to the direct production of the 
sound track without the use of the photographic process or embossing 
or similar methods; The complete equipment requirements for the 
hand animation of sound film are one drawing pen, one bottle of India 
ink, clear film, and a film holder. 

The production of controlled pitch may be accomplished by the use 
of the sprocket holes for the basic reference as to wavelength. Thus, 
one, two, or four lines per sprocket hole will, on running, demonstrate 
that the four is an octave higher than the two, which is also an octave 





1 V 









II / 


/ IK 



/ II 



/ UK 


Fig. 1 The placing of marks along the sound 
track enables the control of rhythm. By rotation 
of the azimuth, a mark may be softened, though 
the same effect may be achieved by the change of 
inks, stroke length, and other factors. 

higher than one. Such a process may be expanded such that, for 
example, five notes each an octave apart may be produced. If three 
strokes, instead of two or four, are made to the sprocket hole, the 
result will be a musical interval of a fifth above the bottom note. 
By six or twelve strokes and so on, a crude musical may be produced. 

By spacing marks along the sound track and repeating the spacing 
again and again, it is possible to produce percussive effects and 
rhythms. (See Fig. 1.) By the construction of loops of film with 
sample rhythms, a continuous rhythm is possible, enabling repeated 
study of a drawing without the labor of redrawing successively. 

Several methods of control of the volume of the drawn tones are 
possible. By the use of blue writing ink in place of black India ink, 
a definitely quieter sound will result, depending on the color sensi- 
tivity of the reproducing photocell surface. Thus, by the use of 
colored inks, it is possible to draw a passage which will reproduce 




differently according to the color response of the system. This may 
be accomplished in a laboratory by means of a variable color source 
such as a monochromator or more simply by the use of color filters. 
This type of tone control is to be differentiated from an electrical tone 
control in that it is possible to control the volume of each sound, and, 
thus, knock out a "green" tone, for instance, by insertion of a green 
filter, while leaving the "red" tones at full modulation. Thus, the 
animator may play back and choose the relative intensity of several 
tones by the choice of color filters in much the same manner that a 
director of an orchestra directs sections of string and wind. 

Fig. 2 Low "do" and high 
"do" are drawn as spaced 
strokes. The basic fan pat- 
tern shows the derivation of 
the spacings. 

Fig. 3 The geometry of 
the basic pattern A/B = 
X/Yj wherein X is the pitch 
spacing of the higher note; 
Y is the pitch spacing of the 
lower note; A and B are the 
Distances corresponding to X 
and Y, respectively. 

If instead of a variable color of ink, a range of ink bottles of various 
gray densities is used, a stroke of black ink would produce a loud 
note ; a dip in middle gray, a medium note ; and the use of the palest 
of the inks, pianissimo. This is a fairly satisfactory, system, though 
with transparent ink it is difficult to prevent some strokes from being 
heavier than others, which results in undesirable irregularity. Varia- 
tion of modulation is also possible by varying the amplitude of the 
stroke, as is obvious. Therefore, it is possible to combine variable- 
area and variable-density methods for a most convenient system: 
black ink for 100 per cent, 75 per cent, 50 per cent, and 25 per cent 
modulation and lighter inks for less than 25 per cent. With this 
range of volumes and the pitch systems described above, the sound 




tracks of the abstract films "Scherzo" and " Loops" were made in New 
York in 1939 for the Museum of Non-Objective Paintings. 

Further improvement of the methods used is possible by the use of 
a diagram or guide which may be placed under the film so that the- 
hand work is made to fit the spaces of the pitch selected. Such a 




Fig. 4 The basis for the fan diagram of Fig. 5, a dia- 
tonic scale (just temperament). 


Fig. 5 A basic fan diagram showing the pitch spac- 
ings for the diatonic scale (just temperament). 

chart or pattern may be viewed by transmitted light, though use by 
reflected light is not impossible. This same method may be used 
to repeat a passage by laying the master under the raw stock and 
hand-copying the master track. 

A basic diagram is shown in Fig. 2 wherein low "do" is drawn as 30 
equally spaced strokes, high "do" also as 30 equally spaced strokes 
at one half the distance. This is based on A/B = x/y of Fig. 3. On 
the assumption that musical intervals have the following ratios 
(Fig. 4); a diagram was built which represented the diatonic scale 




(just temperament), Fig. 5. A section of sound track, Fig. 6, 
was drawn with a stroke for each one on the horizontal lines of the 
diagram. When played, this gives a clearly intoned diatonic scale. 
As this includes the interval of the semitone, there appears to be no 
reason why one could not draw a chromatic scale as well. 

As the simplest ratios were used in the above diagrams, the scale 
that resulted was in just temperament. This is rather troublesome 

Do | Re | Mi | Fa | Sol | La | Ti | s Do 

Fig. 6 A sound track showing a climbing scale. 


Fig. 7 A basic fan diagram for an 
equally tempered scale. Comparison 
between this fan diagram and that for 
the diatonic shows the differences 
quite clearly. 

for any great use of chromatic passages or key modulation. There- 
fore, an equally tempered scale was produced, Fig. 7. 

The development of quarter tones is possible but is an even greater 
amount of work. With five chromatic octaves of pitches and about 
ten degrees of volume, the remaining quality requiring control is the 
tone or wave form itself. For example, all the tracks of Fig. 8 have 
the same pitch, but different qualities of sound. To create a definite 


timbre, it is necessary to make each stroke the same in shape, as the 
slightest variation from stroke to stroke tends to create an un- 
desirable noise. 

As a minute change in the shape of the stroke creates a radically 
different timbre, there is a definite problem as the drawing is done on 
an extremely small scale. The accuracy of visual observation by 
itself is not adequate, but when combined with the much greater 
precision of the hand and fingers -, one can execute extremely fine 
changes of pressure and location, so that if strokes are made in rapid 
succession one beside the other, the hand develops a kind of muscu- 
lar memory. Only if the hand moves or lifts away to dip into a 
bottle of ink is the muscular memory broken, such that it is im- 
possible to make the same shape of stroke. By experimenting in 

i i i i i i l l l l 

<l I I I I I l l I I I I 


Fig. & All the tracks shown are of 
the same pitch, though they exhibit 
different qualities o'f sound. 

a trial-andrerror way with different types of pens and brushes, as 
well as ways of holding them, one can discover a number of differ- 
ent timbres, which when the muscular memory is trained may be re- 
produced on film at will. 

As observed previously, a piece of photographically recorded sound 
track (variable-area) provides the temptation for hand imitation. 
To date, efforts at hand imitation have shown that it -is an utterly 
hopeless method of arriving at any kind of synthetic sound. The 
photographically recorded track is far too complex and subtle to 
yield to the hand method. This is probably due to the combination 
of phase relations, transients, room acoustics, and other factors which 
yield more readily to synthesis by precise mechanical means which 
can produce pure, sine waves and any number of harmonics as well 
as square and saw-tooth curves. 

The more fruitful method for experimentation in the medium of 


hand-drawn sound is that of building entirely new types of sounds 
which -are the results of the shapes which a pen and brush can draw 

It should be pointed out, however, that it is not so much as a source 
of new timbres, but as a method of controlling rhythm and meter that 
this method of making sound is important. In rembering that one 
second of time is represented by about l l / 2 feet of 35-mm film, it is easy 
to see how complete a control of the time dimension there is. A sound 
can be plotted to at least the nearest 200th of a second if desired. This 
is much finer precision than it at first appears ; it means that one can 
space sound metrically with a precision beyond most other ways of 
making music and considerably beyond the musical-notation system. 
Very intricate rhythm can be evolved by simple geometric spacing 
along the sound track. One rhythm can be set against others con- 
trapuntally. Complex rhythms can be made to reproduce much 
faster than it is possible to perform by the human hand on any in- 
strument; a rhythm can be expanded to last over many seconds, or 
contracted into a space of 1 / 2 o of a second (or to the limit of human 
appreciation, which is about 30 notes per second) . Rhythms can be 
inverted by simply running the sound track backwards, or drawing 
the same metrical spacing in reverse. 

Loops of film, the ratios of whose lengths are carefully planned, 
can be played together to create constantly creeping rhythms which 
repeat themselves at very long intervals of time. 

The contrapuntal use of rhythms can be made in two ways : 

If the rhythms are spacious, they can all be drawn on one track. 

// complex, they are best drawn on two or more separate, but par- 
allel, tracks which are then synchronized and recorded in the usual 
way onto one track. 

The re-recording of several tracks together opens up a veritable vista 
of possibilities, such as rhythms staggered against themselves, re- 
versed, inverted, and the like, and gives over-all control of the volume 
of each strand of rhythm. No microphone, no recording apparatus, 
or studio! The normal complicated technical processes of making a 
sound track have been reduced to surprising simplicity of a drawing, 
and a one-man operation. This worthy goal has many virtues, as 
the personnel needed to make a film, and the accumulation of their 
decisions, gives the film a shape very different from what it would 
have been if the director or originating artist produced the film 


The present state of motion picture engineering is such that from 
the viewpoint of the individual artist, the traditional cinema is a 
cumbersome means of expression'with so much mechanical gadgetry 
and technical processes intervening between the artist's original con- 
ception and the finished product, that it is difficult to finish up with 
one resembling the other. In discarding the traditional microphone 
and studio equipment, it becomes possible to make at least one branch 
of cinematic art a simple and arousing form of artistic expression. 

As the inherent restrictions or limitations of hand-made sound 
tracks as a medium are severe, it seems in order to point out that they 
bear the same relationships to the usual technique of the cinema, as 
mosaics do to oil painting. Therefore, it would seem that restrictions 
are no more a reason for uninteresting work than they are in mosaics ; 
in fact, the peculiarities can often prove a very great advantage. 

In the preceding discussion it has been assumed that the hand- 
work was done directly on the sound track of a 35-mm film. The 
same can be done on 16-mm film directly, but it is not recommended 
under any circumstances as it passes the limits of unaided manual 
skill. In order to attain more controlled wave form, or tonal quality, 
it is possible to go to larger tracks than 35-mm and reduce in re- 
recording onto the release medium. The sound may be drawn 
directly on the film or drawn on cards or paper strips and transferred 
to the film. Such methods, though more complicated, offer some 
attraction and are described in the following sections. * 


The standard sound-on-film recording means, as currently ac- 
cepted, may be adapted to recording synthetic sound purely by the 
connection to the proper electrical circuits. The disadvantage in this 
adaption is, that at the speed of reproduction, it is not possible to 
initiate adequate control of recording to realize the benefits of the 
synthetic-film-recording methods. For this reason, it seems desir- 
able to use methods more specialized and adaptable to the purposes 
of synthetic-sound problems. This moves more closely toward the 
conventional concept of animation. 

The basic and simplest mechanical method consists of frame-by- 
frame exposure of the film in a standard animation camera employing 
a special aperture exposing only the proper lengths of sound track per 
exposure. This method by virtue of the pull-down tolerances, 


shrinkages, and like difficulties, has inherent 24-cycle modulation 
caused by overlap or gap at the end of each exposure. This is the 
major problem of this method and can never be eliminated com- 
pletely without complexities worse than the evil. Partial elimination 
of this difficulty was accomplished by the author by staggering the 
edge of the exposed frame and thereby utilizing the azimuth error 
as a bloop to soften the square-wave form. With care this solution 
will operate sufficiently so that common reproduction systems are 
not disturbed enough to upset the reproduction, but for the critical, 
the solution is not acceptable. The unwary should be cautioned 
optically to center the lens system used in this method, as resolution 
affects the frequency response and will also introduce 24-cycle modu- 
lation in bad cases. For continuous sustained notes, the camera 
may be run continuously. It may also be rewound to enable mul- 
tiple exposure for choir and synthetic-reverberation effects. Various 
types of masks are effective in this system for noise reduction and 
other purposes, such as the separate exposure of separate tracks 
within the scanning areas. 

In order to eliminate 24-cycle modulation, the frequency may be 
demultiplied by exposing multiple lengths of frame simultaneously; 
not necessarily the same length each shot, though usually so. This 
does not eliminate square-wave and saw-tooth trouble but lowers 
their frequency and effectiveness. For some types of composition 
this will reduce the labor, and therefore, it seems advisable to con- 
sider the possibility of a variable-frame-length camera, much on the 
order of some microfilm equipment. 

In order to eliminate absolutely 24-cycle modulation, or multiples, 
continuous exposure of the film is necessary, whether by methods 
similar to optical reduction printers or scanning systems. The 
reproduction system possesses the advantage of being able to use 
directly, cards, drawings, and paper tapes intended for use on the 
animation setup, without change. The problems of gear modulation 
and other speed differentials are ever-present and constitute a hazard 
in this method, not to mention the problems of correctly operating 
and spacing and arranging the cards being reproduced, to avoid 
shift in pitch, loss due to azimuth error, and irregular rhythm. The 
continuous process will probably work best with two operators, 
though the authors have no experience in this line. Continuous 
camera design is also capable of operating directly coupled to a 
harmonic integraph or equivalent in synchronism, controlled by the 


operator as to wave form, amplitude, rhythm, and other musical and 
speech components. 


As previously mentioned, a continuous camera directly coupled to 
a -curve-generating or scanning system is sufficient to produce all 
forms of synthetic sound provided the control is proper, adequate, 
and understood. The best approach from the mathematical stand- 
point is that of synthesizing basically the wave form by a succession 
of sine-wave generators coupled in proper phase, with their frequency 
set for proper harmonics as well as amplitude, and integrated to 
produce the over-all envelope. By continuously varying the ampli- 
tude and frequencies, the wave form can be put through its paces, 
and if as demonstrated by Michelson and Stratton, with 80 elements, 
anything from a square wave to simple sine curve can be generated 
on the harmonic integraph.* Needless to say, though basically sim- 
ple, the mathematical concept of the harmonic integraph requires 
conversion from standard musical score, speech, and voice-tone nota- 
tion and the like in order to be practical. ** 

If it is desired to generate synthetically a wave form already known 
to exist and if photographed or available as a standing wave on an 
oscilloscope, application of harmonic analysis will produce .the neces- 
sary constants to set the harmonic integrator. 

By means of curves generated by the harmonic integraph or similar 
machines (Fig. 9), as well as by hand, it is also possible to photograph 
frame by frame and produce a synthetic sound track. 

It is also possible to retouch, re-edit, and mask, existing sound 
tracks for special purposes. Several unsystematic trials have been 
made using miscellaneous material, such as human faces, photo- 
graphed on the sound track by Moholy-Nagy which are closely 
related to the early block-image methods of the Russian experiments. 
The difficulty with the card or tape method lies in the large size of 
the image required for high-frequency response, unless the card 
is- used only to supply setting data for the generator;- in the same 
manner, the length of a complete cycle of a percussion instrument is 
excessively cumbersome. 

* Brother to the tide-prediction machine, well-known mathematical machine. 
** As far back as 1900 music research developed the practice of recording wave 
form analyzed as to character by means of a Card giving the constants of the equa- 
tion of the wave. 




It is obvious that by means of standard accepted methods, elec- 
trical generation of wave patterns can produce the same result as the 
more mechanical harmonic integraph. The clumsy situation which 
exists with electrical wave-form generations is due to the necessity 
for recording at a slower speed than reproduced in order to be able 
to control the components accurately. Loss of the advantage of 
synthetic sound on film is likely to occur with electrical wave-form 

Fig. 9 The harmonic integraph is to be differenti- 
ated from the analyzer in that the latter reduces known 
tones to the basic components whereas the integraph 
synthesizes these basic components into an integrated 
and recorded wave form. Shown schematically is a 
very simple generator consisting of a drive on two 
crank eccentrics in harmonic relation (shown out of 
phase) . The output of the cranks is added by the pul- 
leys on the string which in turn operates the recording 
system? driven interlocked with the crank drive. The 
strength of each harmonic is regulated by the leverage 
on the recording mirror. A basic weakness in this type 
of machine is the virtual impossibility of any transient 

generation because of the difficulty in obtaining duplicates of unsus- 
tained notes such as percussion and transitory phenomenon. 

General Problems 

The general problems of picture animation apply to those of sound 
animation, namely, system, accuracy, and perseverance. The elimina- 
tion of paper shrinkage and warp is a necessary, prerequisite to pho- 
tography of the frame-by-frame method of sound. Calibration and 


measurement of all components involved is taken for granted, though 
it may well be the major amount of labor.* 

The maintenance of pitch and tonal relationships is inherently one 
of measurement. Alignment and placing of cards and tapes can and 
do exercise too great an influence for normal consideration, and 
should be solved very carefully before extensive efforts are laid out. 
The azimuth error introduced in hand drawings and cocked cards 
must be eliminated to control results. 

Musical notation as currently used does not specify tones, nor 
timing, nor decibel level precisely enough that artistic interpretation 
is not necessary for acceptable transcription. In conversations with 
composers, it was found that a more precise notation or addition to 
present notations is required, human inertia being the chief barrier. 
Musical notation will not adequately handle unsung speech and sound 
effects and therefore, it is obvious that the mathematical notation 
system previously referred to in connection with the harmonic in- 
tegraph, though lengthy, has of necessity some place in the system. 

The choice of tone, namely, composite wave pattern may be ex- 
pedited by the use of a card catalogue either indexing general patterns 
by work description or by loops to be run to hear the tone. Doubt- 
less, the gadgeteer can devise punch-card systems to set the harmonic 
integraph automatically and thereby mechanize the labor, though 
it seems advisable that synthetic-sound systems eventually should 
be conceived and constructed in such a manner that initial capital 
investment is small enough to enable those who are of moderate 
financial status, and students of musical composition to have the 
opportunity to study more directly,** 

At this point, it seems rational to predict that" frame-by-frame 
animation is a logical beginning point for experimentation, and that 
the cheapest forms of equipment should be supplied to fill this order. 
Driven continuous equipment seems to be the other possible be- 
ginner's stage, especially in consideration of the length required for 
complete recording of transients, percussion, and the equivalent. 
The addition, at a later date, to the beginning equipment of the con- 
tinuous type may be made by substituting a scanning system driven 

* Optical distortion and magnification, lines-per-millimeter resolution, stray 
light or fog, and curvature of field, all should be known or measured, likewise un- 

** Re-recording seems advisable for various types of tracks to allow freedom 
in synthesizing. 


by a harmonic integraph which may always be removed, for direct 
photography of already drawn patterns. The addition of punch- 
card control to the integraph is such that composition would become 
card-shuffling and film-changing with the exception of unsystematic 
patterns still requiring direct photography from tapes. In this re- 
spect, it seems probable that the animation of sound will not reach 
the laborious stage of picture animation, what with the repetition of 
passages and the possibility of recording partial passages consecu- 
tively by means of masks allowing separate exposure of separate 
tracks side by side within the scanning area. 

Without the maintenance of maximum flexibility, that is, the 
ability to record a very wide variety of types of sound, it is possible 
to conceive that the whole concept of synthetic sound on film be- 
comes limited and serves no better purpose than present-day elec- 
tronic organs, and the like. The advantage of the system is not 
necessarily only the introduction of new sounds but also that of 
assistance to the composer in assurance that his score will be heard 
as composed and not rearranged beyond recognition. This we do 
not conceive as technical unemployment for the musician, but rather 
an assurance that proper rendition will be appreciated. It is prob- 
able that many synthetic-sound compositions may never be heard 
publicly, but used rather as training and prompting in the rendition of 
difficult passages of a standard score. As a supplementary device to 
standard musical training, a synthetic-sound installation should 
enable a student of music to hear his own work as "played" by sym- 
phony, chamber, or "boogie", according to his choice in generating the 

original film. 


(1) John and James Whitney, "Audio visual music," p. 31 in A rt in Cinema, 
by Art in Cinema Society, San Francisco Museum of Art, 1947, edited by Frank 

(2) John Serrano, "Abstract film explorations in 16 mm color and sound," 
Home Movies, p. 412; July, 1947. Describes work of John and James Whitney. 

(3) Frederick W. Kranz, "A mechanical synthesizer and analyzer," Jour. Frank. 
Inst., August, 1927. Describes a harmonic synthesizer of 40 harmonics located at 
Riverbank Acoustical Laboratories of Armour Research Foundation,' at Geneva, 

(4) Leon Becker, "Synthetic sound and abstract image," Hollywood Quarterly, 
vol. 1, no. 1; October, 1945. 

Industrial Control Applied to the 
Projection Room* 


Summary An improved method of adapting industrial control to pic- 
ture and sound projection is described. Master-control stations located be- 
low the booth viewing ports place push buttons at the projectionist's finger 
tips. These remotely operate the various apparatus in sequence as selected. 
An integrating intercommunication unit provides reliable contact between 
projection booth and auditorium. 

THE MOTION PICTURE studio projection room, even today, is 
handicapped by some of the early practices established during 
the transition from silent to sound motion pictures. As an example, 


Fig. 1 Completed projection room. 

* Presented October 22, 1947, at the SMPE Convention in New York. 



criticism may be directed at 
the lack of uniformity in regard 
to control. In many instances, 
the location and arrangement 
of controls have made good 
operation exceedingly difficult. 
In the studios, projectionists 
are expected to operate with 
equal skill in any of the various 
booths. Standardization, then, 
is desirable. 

Careful planning in the de- 
sign and placement of essential 
control apparatus' provides im- 
proved programming. In ad- 
dition to the generally accepted 
good engineering practices, an 
analysis of operational func- 
tions indicated the necessity of 

Fig. 3 Master-control console open for 

Fig. 2 Master-control console. 

including (1) centralized re- 
mote-control stations, designed 
and located to provide smooth, 
rapid utility; (2) flexibility of 
apparatus in relation to main- 
tenance and routine testing; and 
(3) a satisfactory method of 
communication between the 
auditorium or theater and pro- 
jection booth, permitting the 
operator to receive or impart 
instructions without handling 
an instrument. 

The projection room shown 
in Fig. 1 was recently placed in 
service at the West Coast 
Studios of Paramount Pictures, 
Inc. The ceiling as well as 
the front wall is treated with 
acoustical tile to the trim line. 
The lower . section is covered 




with sectional, removable sheet-metal panels. These cover plates 
are an excellent fire wall and provide access to conduit junction boxes 
and raceways. This room was equipped with four soundheads, two 
associated with the projectors and the other two for sound-track re- 
production only. Conventional mixing facilities may be remoted to 
the review room for preview or editing rehearsal if desired. 

Adjacent and to the right of each projector is located a master- 

Fig. 4 Remote-operated equipment. 

control station as shown in Fig. 2. Duplicate control facilities are 
available from the two operating positions. These units are located 
directly below the viewing port, conveniently placing the essential 
controls at the projectionist's finger tips. Grouped in sequence on 
the sloping surfaces of these units are transparent plastic push but- 
tons. These buttons are illuminated when operated in the "on" 

Fig. 3 shows one of the master consoles with the front cover re- 
moved and the control unit opened for inspection. Machine selec- 
tion, distributor selection, the starting and stopping of interlock 
motors, the douser, signal, and annunciator gear as well as house 
lights are controlled from this station. The house-light contactor 
may be used to control saturable reactors and additional sequence 




relays affording automatic dimming of lights in the auditorium, the 
opening of the screen curtains, and other desirable effects. 

Suspended below are the preamplifier, postequalizer, and associ- 
ated filter. The amplifier is isolated from the console frame to pre- 
vent vibration that might cause microphonics. Above this amplifier 
is located a compartment for headphones and tools, dubbed by its 

Fig. 5 Small console. 

users as the "glove" compartment. The accessibility of the various 
components in relation to replacement and ease of testing received 
careful consideration. 

The relays, contactors, lamp rectifiers, and associated power equip- 
ment controlled by these stations are located under the floor of the 
booth. Fig. 4 illustrates a portion of the remote-operated installa- 
tions. Each relay and contactor is individually shock-mounted. 
These components are mounted on a base plate which in turn is shock- 

252 BOYCE AND HYTEN % March 

mounted. With the sound- and dustproofed cover in place, no con- 
tribution is made to the aural noise level. This grouping of control 
relays and contractors is of great value in regard to maintenance. 
A meter and a few jumpers permit the rapid analysis of the various 
circuit functions. 

Fig. 6 Amplifier rack and test panel. 

One of the small consoles associated with the sound (dummy) pro- 
jectors may be seen in Fig. 5. These units house preamplifiers, 
postequalizers, and associated filters. The push buttons on the top 
of the enclosures are multiples of the booth to auditorium signal 

The main amplifier, power amplifier and associated time delay, 
booth monitor amplifier, and the regulated power supply for the 


remote preamplifiers as well as the test and lineup equipment are 
mounted in the rack shown in Fig. 6. This equipment, in addition to 
the regulated exciter-lamp power supplies, is energized at the touch 
of a push button located on the control panel. A "ready" light sig- 
nals the completion of the plate time-delay cycle. 

Communication between the review room and the booth was de- 
signed to relieve the operator of any manual operation that might de- 
tract from his duties. On the desk in the re view, room is located a 
conventional desk handset. When it is removed from its cradle, the 
booth monitoring is automatically heavily attenuated and a signal 
light alerts the projectionist. By the pressing of a button on the 
handset, the operator may be instructed by the executives or editors 
using the room. As the button is released, the booth operator may 
reply. Returning the handset to the cradle normals the projection- 
booth monitoring level and disconnects the signal light. The pro- 
jectionist establishes contact with the review room by pressing a button 
that flashes an indicator on the review-room desk. Should this sig- 
nal go unnoticed, a second button is available for sounding a warning 

The operating ease with which this improved equipment performs 
indicates a growing acceptance of simplified automatic controls wher- 
ever applicable throughout both studio and theaters. 

Review of SMPE Work on 
Screen Brightness 

THE QUESTION of screen brightness became one of paramount im- 
portance shortly after the advent of sound motion pictures at the 
time processing control was being greatly improved and the industry 
was becoming uncomfortably aware of the complicated relations 
between print density, contrast, screen size, brightness, reflectivity, 
and auditorium illumination as related to audience viewing comfort. 
Numerous papers and committee reports published in the JOURNAL 
since 1931 have contributed greatly to the industry's understanding 
of the problem and represent most of the accumulated knowledge of 
the subject. This information was consulted prior to adoption of the 
present standard screen brightness level of 10 foot-lamberts which was 
approved by the American Standards Association as American Stand- 
ard Z22.39 in May, 1944. For all the fine work done up to now 
however, the present American Standard is the only specific recom- 
mendation to have evolved but had the war jiot interrupted the 
Screen-Brightness Committee's program, undoubtedly much more 
would have been accomplished, particularly in both screen illumina- 
tion and screen-brightness measurement. 

The industry is attempting seriously to define audience viewing 
comfort in a postive way, so that at least a few of the many basic 
variables can be specified and, where possible, standardized. Among 
the factors that it seems desirable to specify are print density, print 
contrast, projection-light intensity and spectral quality, light dis- 
tribution, screen brightness, #nd auditorium illumination. In ad- 
dition, these are factors over which there is a. reasonably precise 
degree of control and it is convenient that they lend themselves 
readily to measurement and that scientific language has provided 
the necessary nomenclature as well as accompanying units of measure. 
Therefore, specifying these factors is relatively simple when com- 
pared with defining the many intangibles that characterize visual 
enjoyment of motion pictures. 

Since it is possible to make definite observations, record what is 
observed, and also to control several elements of the system, almost 
' any given set of viewing conditions can be reproduced later for further 
study or investigation. It was for this reason that the committee 


decided to consider only these controllable elements in the present 
program, which has been restricted in scope in order to hold the 
demands on the part of individual committee members to a minimum 
and to establish goals that the committee might reach in some 
reasonable period of time. 

The three following items make up the Screen-Brightness Com- 
mittee's long-range program. The first is the one with which the 
committee is currently occupied. 

1. Determine present theater practice for screen illumination, 
screen reflectivity, and screen brightness. 

2. Evaluate present use of projection equipment and screens from 
the standpoint of over-all efficiency. 

3. From the data and experience gained in the above work, pre- 
pare specifications for intensity and brightness-measuring instru- 
ments; outline a standard procedure to be used in making these 
measurements and then establish a new standard for screen-brightness 
level, specifying desirable levels of auditorium illumination, brightness 
distribution, and so forth. 

In order to determine present practice in a reliable way, the com- 
mittee feels it is necessary first to agree on particular measuring in- 
struments and the procedure for their use; then make measurements 
in enough of the country's 19,000 theaters for the results to be con- 

The following brief specifications for illumination and brightness- 
measuring instruments, prepared in 1942, were then the committee's 
recommendations and are quoted here with a word of explanation, from 
the January, 1942, JOURNAL. 


Illumination Brightness Meter 


Useful range of instruments . 2-50 foot- . 5-30 foot-lam- 
candles berts (or 4-30) 

Accuracy of measured values 



Reproducibility of measured values 



Maximum screen area or angle to be included 

by instruments 

1 sq ft 

3 (preferably 2) 

Maximum price 





" . . readable brightness values from 0.5 to 30 foot-lamberts (were) 
included provisionally to permit measurement of the brightness of the 
peripheral field should that area, be illuminated. The alternative 
range of values from 4 to 30 foot-lamberts was included, if it should 
be found impracticable to obtain an instrument capable of reading 
0.5 foot-lambert. 

"The values for the illumination meter of from 0.2 to 50 foot- 
candles were chosen in recognition of the requirement in some states 
of minimum ambient levels of illumination in theater auditoriums, 
and because of the numerous other illumination measurements for 
which such an instrument could be used in theaters." 

Commercially available illumination instruments that have suit- 
able sensitivity and spectral characteristics for measuring light in- 
cident on the screen could be used in a survey at the present time, 
.with some modifications, but brightness meters are a more serious 
problem. The MacBeth Illuminometer and Luckiesh-Taylor visual 
comparison instruments are well known but are difficult to use for 
theater-screen work because color differences in the comparison field 
make the apparent brightness match so much a function of the observ- 
er's individual eye "sensitivity that two observers rarely read the same 
values without recalibration of the instrument. Correlation of 
results is not easy, even in the hands of experienced operators, so the 
previous committee recommended that a photoelectric type of in- 
strument with the proper spectral and sensitivity characteristics be 
developed for the brightness phase of the survey because the results 
would be practically independent of human error. The present 
committee concurs and is now considering tentative specifications for 
a combination brightness-and-illumination instrument. 

A combination photoelectric instrument to read such extremely 
low brightness levels will require a long time for development, so the 
committee felt it undesirable to wait and further delay its work, be- 
cause the need for the survey information is so urgent. Therefore, 
to get things started, the first item on the agenda was divided into 
several parts* in order that more than one phase of the work might 
proceed concurrently. 

1. Conduct a preliminary survey to prove practicability of pro- 
cedures and value of results. (This has been done and is the subject 
of the report of the Screen-Brightness Committee which follows this 


2. Develop new brightness meters. (New instruments are now 
in the process of development and will be described in a following 
issue of the JOURNAL.) 

3. Prepare a simplified survey procedure. (The Committee's 
current recommended procedure is described in the Report of the 

4. Conduct a complete theater survey using new instruments and 
the approved procedures that have grown out of the preliminary 


Several questions which merit further consideration but are of such 
a nature that they must be held for a later date, were published in a 
Screen-Brightness Committee report on page 127, of the August, 
1936, JOURNAL. In addition to those mentioned above, they are 
substantially as follows : 

1. What correlation is there between best print contrast and 
screen brightness? 

2. What effect does the brightness standard have upon the stand- 
ard of release-print quality? Shall release prints of different con- 
trasts be made available to theaters operating at different screen- 
brightness levels? 

3. Is high-light density, average density, shadow density, density 
of the area of principal interest, or a combination of these factors 
the thing that determines preferred brightness? 

4. What possibilities are there for improvement in projection 
optics, pull-down efficiency, and source brilliance? 

5. What is the effect of color of the light. source, color of the screen, 
and color of the print upon the desired brightness? 

6. What proportion of moving picture goers see pictures on screens 
greater than 20 feet, 25 feet, 30 feet? Statistical data on theater 
sizes, screen sizes, projection equipment, and attendance figures are 
needed by the Committee. A complete paper of this kind would be 
valuable also in connection with other problems confronting the 

7. What factors determine screen width? Would it not be better, 
for instance, to use a 25-foot screen at 9 foot-lamberts than a 30-foot 
screen at 7 foot-lamberts? The data of visual acuity tell us that the 
picture detail visible at great viewing distances should not suffer. 

8. What is the effect of auditorium illumination upon the re- 
quired brightness level? 


9. What is the effect of the visual angle or the screen size upon 
this value? 


(1). "Report of the theater engineering committee," /. Soc. Mot. Pict. Eng., 
vol. 1, p. 74; January, 1942. 

Report on proposed instrument for measuring illumination and 
screen brightness. 

(2). "Report of the projection practice committee," J. Soc. Mot. Pict. Eng., 
vol. 1, p. 39; July, 1937. 

Recommends that previously proposed screen illumination test film 
not be used. 

(3). "Report of the projection screen-brightness committee," /. Soc. Mot. 
Pict. Eng., vol. 2, p. 127; August, 1936. 

Resume of the screen-brightness Committee's work, summary of 
previous material on the subject, conclusions recommending adop- 
tion of substantially the present standard, and a statement of exist- 
ing problems that remain to be solved. 

(4). "Report of the committee on projection screens," /. Soc. Mot. Pict. Eng., 
vol. 20, p. 510; June, 1933. 

Proposed comparison method for determining screen reflectivity n 
the theater, includes reflection factor samples. 

(5). A. A. Cook, "A review of projector and screen characteristics, and their 
effects upon screen brightness," /. Soc. Mot. Pict. Eng., vol. 26, p. 522; May, 1936. 
Theoretical efficiency of modern projector optical systems and com- 
puted screen brightness. 

(6). E. M. Lowry, "Screen brightness and the visual functions,'" /. Soc. Mot. 
Pict. Eng., vol. 26, p. 490; May, 1936. 

Relation of object size, contrast, illumination intensity, and visual 
exposure time in the study of human vision, with numerous refer- 

(7). F. K. Moss and M. Luckiesh, "The motion picture screen as a lighting 
problem," /. Soc. Mot. Pict. Eng., vol. 26, p. 578; May, 1936. 

A statement of several phases of the problem of screen illumination 
and suggestions for further study leading tpward improvement. 

(8). M. R. Null, W. W. Lozier, and D. B. Joy, "The color of light on the pro- 
jection screen," J. Soc. Mot. Pict. Eng., vol. 3, p. 219; March, 1942. 

Measurements of the spectral-energy distribution of light on the 

(9). O. Reeb, "A consideration of the screen-brightness problem," J. Soc. 
Mot. Pict. Eng., vol. 5, p. 485; May, 1939. 

Report of a German survey recommending an interim screen bright- 
ness standard of 8' f oot-lamberts and proposes further theater sur- 


(10). R. P. Teele, "Photometry and brightness measurements," J. Soc. Mot. 
Pict. Eng., vol. 26, p. 554; May, 1936. 

General data on screen brightness. 

(11). C. M. Tuttle, "Density measurements of release prints," J. Soc. Mot. 
Pict. Eng., vol. 26, p. 548; May, 1936. 

Light-transmittance characteristics of release prints and their signi- 
ficance as related to the study of screen illumination. 

(12). C. M. Tuttle, B. C. Hiatt, and B. O'Brien, "An experimental investiga- 
tion of projection screen brightness," J. Soc. Mot. Pict. Eng., vol. 26, p. 505; May, 

Average observer's choice of screen brightness and contrast between 

picture and screen border. 

(13). A. T. Williams and W. F. Little, "Re'sume" of methods of determining 
screen brightness and reflectance," /. Soc. Mot. Pict. Eng., vol. 26, p. 570; May, 

Importance of auditorium illumination and screen brightness, and 
methods of measuring both brightness and reflectance. 

(14). S. K. Wolf, "An analysis of theater and screen-illumination data," 
/. Soc. Mot. Pict. Eng., vol. 26, p. 532; May, 1936. 

Review and summary of theater and screen-illumination data previ- 
ously published, with a valuable list of references. 

(15). R. J. Zavesky, C. J. Gertiser, and W. W. Lozier, "Screen illumination 
with carbon-arc motion picture projection systems," J. Soc. Mot. Pict. Eng., vol. 
48, p. 73; January, 1947. 

Present-day carbon-arc projection systems and the amount of light 
they project are described with curves for determining illumination 
intensities on various sizes of screens. Reference is made to the 
applicable American Standard on Screen Brightness. 

Executive Secretary 

Report of 

Screen-Brightness Committee* 

THE COMMITTEE has actively embarked on a preliminar3 T survey of 
a number of representative theaters to determine practical meth- 
ods for measuring brightness and illumination of motion picture 
screens. Equipment and test procedures immediately available were 
used to expedite the initial task of investigating in a few theaters 
proper measuring techniques, and of determining present brightness 
and intensity levels in theaters. 

The immediate purpose of the committee's program is to gain 
enough experience concerning specific test procedures to be able to 
recommend techniques to be used in a more complete survey aimed 
at obtaining basic information regarding screen illumination and 
brightness practice in the entire industry. With information avail- 
able on test methods and present theater practice, it will be possible 
for the industry and the committee to utilize theater equipment most 
effectively to achieve desirable standards of brightness. 

This progress report deals specifically with the preliminary survey 
limited to eighteen theaters in the East and Middle West. The com- 
mittee was very much pleased with the active co-operation afforded 
by the projectionists, the theater managers, and all other groups 
connected with the theater survey. 

Acknowledgment is due also to the Bell and'Howell, Eastman 
Kodak, General Electric, and National Carbon Companies for supply- 
ing the necessary equipment for conducting the survey. 


It was the decision of the committee that in order to obtain com- 
plete data for over-all usefulness, it would be necessary to measure 
the light intensity on the screen, the brightness of the screen, and to 
record some of the physical dimensions of the theater affecting pro- 
jection, and some of the details regarding projection equipment. 

The measurement of screen illumination was made with each pro- 
jector separately, with operation entirely normal except for the ab- 
sence of film. The light intensity was measured at various points on 
the screen to determine the distribution of the intensity over the 

* Presented October 22, 1947, at the SMPE Convention in New York. 



surface and also to be able to compute the total lumens incident on 
the screen. Two different methods of doing this were employed. 
The one involved a division of the screen area into twelve equal areas. 






. C 




1\ ' 

H f 


# * 















Fig. 1 Sample data sheet for determining screen illumination by the 
12-point method. 

with the light intensity being measured at the center of each one 
of these zones. Fig. 1 describes this 12-point method and shows the 
form of the data sheet used to record the measurements. The other 
method consisted in measuring the light intensity at the center of the 
screen, at the upper left- and lower right-hand corners, and at the 



















SCREEN LUMENS' (1) (2) = ' 



A x 2 = 

2 _ 


WEIGHTED AVG. 121*1 * 

Fig. 2 Sample data sheet for determining screen illumination by the 5-point 


right and left edges midway between the top and bottom of the 
screen. The 5-point method is illustrated in Fig. 2. The committee 
decided to use two methods in this preliminary survey to determine 
whether the method of 12 equal areas could be supplanted with no 
loss in accuracy by a quicker 5-, rather than 12-point measurement. 








A . 


A . 







Fig. 3 Sample data sheet showing location of points for brightness 

The equipment used to determine screen-light intensity consisted 
of a Weston "Photronic" cell corrected for eye sensitivity, and a 
microammeter, with the cell and meter calibrated in foot-candles. 
The cell was placed parallel to the screen facing the projector and 
the determination of incident foot-candles was made from the meter 
calibration at the various spots discussed and illustrated on the data 




sheets. A telescoping pole capable of being extended 20 feet was 
used to advantage to raise the cell to the proper position on the 
screen. A tripod mounting equipped with casters facilitated the 
movement of the telescoping pole across the theater stage. 





H , W 










(a) f/ NUMBER _ 













Fig. 4 Sample data sheet for recording theater data. 

Screen brightness was determined at the time screen-intensity 
measurements were being made. The brightness measurements 
were made at the center of the screen and at the upper left- and lower 
right-hand corners from four positions in the theater. The four posi- 
tions as shown on the data sheet reproduced in Fig. 3 were in the 




center of the theater 3 x /2 screen widths back of the screen, in the 
center of the first row of seats, the extreme left seat in the first row, 
and the seat in the middle of. the row farthest away from the screen 
in the highest balcony, if there was one. A Luckiesh-Taylor meter 
was employed to determine the screen brightness. Since only visual 
types of meters were immediately available the committee decided 
to utilize this type in the survey to permit concrete data to be ob- 
tained without too much delay. However, it is the intent of the 
committee to stimulate the development of physical brightness- 
measuring meters since it is felt that the visual type is not generally 
satisfactory because of the difficulty due to color differences in the 
photometer field. 

X O 








<= 4.0 6.5 9.0 11.5 140 16.5 


6.5 9.0 11.5 14.0 16.5 19-0 



Fig. 5 Range of screen brightness obtained in the 

Among the more important theater characteristics which were 
measured and noted were the screen width and height, the seating 
plan with relation to the screen, that is, the distance from the screen 
to first and last rows, the width of the theater at the first and the last 
row, and the seating capacity. Data on projection equipment were 
also obtained and these included among other things the projection 
throw, projection angle, the type of lens, shutter, arc, and power 
supply. The data sheet used is illustrated in Fig. 4. 


The results obtained in the preliminary survey of the 18 theaters 
were representative of houses having screens in the range from 12 feet 
to 31 feet wide with seating capacities from 300 to 6200 seats and with 




projection throws from 65 to 207 feet at projection angles from 5 to 24 

It was of particular interest to the committee to compare the results 
obtained on screen brightness with the 9- to 14-foot-lambert stand- 
ard now in effect. After the brightness data were analyzed, one 
fact stood out. Approximately 50 per cent of the theaters had a 
screen brightness at or .below the. minimum recommended value. 
The data are summarized in Fig. 5 where there is plotted the per- 
centages of the projectors there were 40 projectors in the 18 theaters 
which resulted in screen brightnesses in the indicated ranges. Only 
12.5 per cent (5 projectors) exceeded the recommended maximum. 

I 30 
uj O 

53 2S 

2 <r 

u. & 
O D 



6.5 8.5 10.5 
8-5 10.5 12.5 





22.5 24.5 
24.5 26.5 



Fig. 6 Range of foot-candles incident intensity obtained 
in the survey. 

Of interest to the committee also, was the light-intensity distri- 
bution over the screen and the total lumens on the screen. The foot- 
candle intensity at the center of the screen in these 18 theaters, 
varied from a minimum of 7 to a maximum of 30. The range of 
incident foot-candle intensities is shown in Fig. 6. Approximately 
one half of the projectors gave from 10.5 to 16.5 foot-candles. 

An analysis of the distribution of light intensity over the screen 
showed that about two thirds of the projectors provided 50 to 75 
per cent as much light at the sides as at the center. One projector 
provided only one third as much light at the side as at the center and 
in three cases the ratio was over 90 per cent. The ratio of corner- 
to-center light generally fell in the range 45 to 65 per cent, although 
in one case it was as low as 25 per cent and at the other extreme ran 
as high as 75 per cent. 




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The total luminous flux falling on the screens was calculated using 
both the 12-point and 5-point methods. The data are summarized 
in Table I. The results show no significant difference between the 
two methods, the average ratio of all results being 1.00. Because of 
this finding and the fact that the 5-point method is faster and simpler, 
the committee is inclined toward its use. 

Estimates were also made of the screen lumens expected to be 
available on the basis of our knowledge of the equipment in use in 
each theater and the measurements recently published 1 on expected 
output of various types of projection systems. Generally, it was 
found that the screen lumens obtained fell below the expected values. 


55 65 75 85 95 


65 75 85 95 100 



Fig. 7 Ratio of screen lumens observed in survey to 
that estimated available from laboratory measurements 1 
on same type equipment. 

The ratio of the screen lumens actually obtained to the expected val- 
ues are shown in Fig. 7. Seventeen and one half per cent of the pro- 
jectors obtained practically all the light to be expected from their 
equipment. On the other end of the scale, 7.5 were obtaining only 35 
to 45 per cent of that estimated obtainable. About half of the cases re- 
sulted in from 35 to 75 per cent of the expected light wjiile the other 
half obtained between 75 per cent and all of the light available. The 
reason for these deficiencies were not determined. However, it is felt 
that proper search would lead to corrections to minimize these 
differences. . 

With data available on light intensity on the center of the screen 
and brightness at the center, it was possible to calculate reflectivity 
for the matte screens encountered in the 18 theaters. The results are 




shown in Fig. 8. The general average level of the reflectivity of the 
screens was approximately 70 per cent. Accurate reflectivity figures 
in individual cases were limited by difficulties in obtaining good vis- 
ual-brightness values with the visual-brightness meter. This un- 
doubtedly is partly responsible for the extremely high values of reflec- 
tivity in two theaters and possibly some of the low values, though in 
this case, deterioration is visualized as the major factor. 


It is recognized, of course, that the results obtained in a prelimi- 
nary survey of 18 theaters are not conclusive evidence of the experience 
to be found in the approximately 19,000 theaters in the country. 

o tn 








45 TO 55 55 TO 65 65 TO 75 75 TO 85 85 TO 95 


8 Range of screen reflectivities obtained in the 

Therefore, this progress report is only indicative rather than conclu- 
sive and must be followed by a more thorough examination on rather 
sound statistical grounds before any conclusions can be drawn regard- 
ing the average brightness and illumination figures representative of 
motion picture practice today. Neither can the committee make defi- 
nite recommendations yet concerning the technique to be used, par- 
ticularly in the determination of screen brightness. The committee 
believes now that a truly successful and most useful brightness meter 
for motion picture survey usage should be a physical measuring de- 
vice rather than a visual photometer. At least two manufacturers are 
engaged in the development of such instruments and the committee 
will examine these units to determine their practicability for the task 


Although definite plans have not yet been formulated, it is the hope 
and intent of the committee that this work be continued more exten- 
sively to arrive at the objectives of specifying equipment and test 
methods for accurately measuring brightness and illumination on the 
screen and of determining present practice in the theaters. It is be- 
lieved the industry will then be in a proper position to make the most 
effective utilization of available equipment and to maintain screen 
lighting in line with recommended practice. 


E. R. GEIB, Chairman 





*Advisory members. 


(1) R. J. Zavesky, C. J. Gertiser, and W. W. Lozier, "Screen illumination with 
carbon-arc motion picture projection systems," J. Soc. Mot. Pict. Eng., vol. 48, p. 
73; January, 1947. 


MR. HENRY GREENSPOON: Has the Committee established what would be a 
desirable screen brightness for theaters? 

MR. R. J. ZAVESKY: The present standard is 9 to 14 foot-lamberts as measured 
at the center of the screen, with the projector running but with no film in the gate. 
Whether that standard will be changed I am not prepared to say. 

MR. ABE KESSLER: As I understand, all the concerns that sell equipment 
motors, generators, rectifiers, projectors are not equipped to advise a man who is 
going to build a theater and who comes to the supply houses for advice. They are 
not equipped to advise him just what to get for a different throw considering the 
size of the house, and other matters. 

Why should they not be supplied with proper information? They should know 
the right type of equipment to sell. 

MR. ZAVESKY: By finding out the present practice in theaters, by proper 
measuring instruments, and by knowing what each piece of equipment will deliver, 
it will be a natural evolution that that sort of thing will occur: the equipment in 
the theater will be matched to meet the standards set up by the SMPE. 

MR. RONALD BINGHAM: Knowledge of the surrounding brightness is very im- 
portant in interpreting the data such as you have given. Is there any intent on 
the part of the Committee to gather data on the screen-brightness level, excluding 
projected light? 

MR. ZAVESKY: That- is part of the longer-range objective of the committee, 
bnt it has not been a part of the immediate program. The initial phases are 


aimed mainly at determining what methods and equipment should be used to 
measure brightness and illumination and to determine what is the present prac- 
tice. Some of those other things we all hope will come along a little later in the 

MR. MATTHEW J. KEEHAN: I assume that during the course of your survey 
you did not visit any studios. Do you intend to do so? 

MR. ZAVESKY: Not at the present moment. The main intent is to determine 
the practice in motion picture theaters. 

MR. JOHN FERGUSON: There was one point on which I was not exactly clear. 
You mentioned that 50 per cent of the theaters were getting 75 per cent of the 
available light. Do you mean that there were misadjustments in the equipment 
or do you mean that the equipment was rated at a higher rating than the theater 
actually was using? 

MR. ZAVESKY: Data have been published in the JOURNAL indicating the total 
quantity of light that could be expected from various combinations of arcs and 
optical systems. Those data were taken into consideration along with the exact 
projection equipment in the theater, and the ratio of that which could be expected 
to that which was actually measured was shown in Fig. 7. The committee did 
not investigate why that difference occurred. 

MR. BEN SCHLANGER: The factor of the screen itself and the light coming 
from it represent additional items that are elusive. I wonder if this report will 
include that eventually? One is the age of the screen; two, the location of the 
screen, the atmospheric condition; three, the polar characteristic of the screen. 

Unless we investigate all of these things, the changing factor of what you are 
getting off that screen is amazing. Unless we add those data we do not know 
what actually is getting to the people's eyes. 

MR. ZAVESKY: The age of the screen with its condition was not specifically in- 
vestigated. The committee went into the theater and measured what the condi- 
tion was at the moment. Whether it was a new screen or an old, a dirty screen or 
a clean screen was not taken into consideration. 

With reference to the condition of the atmosphere: Since all these measure- 
ments were made without any people in the house I suppose we could assume that 
the atmospheric conditions were best. 

We expected to consider the polar characteristic and we still hope that the in- 
formation that we have will show that. You will recall the slide on which wa^ 
shown where and how the brightness was measured The brightness reading was 
taken at the center of the screen and at the upper left- and lower right-hand 
corners, from four extreme positions in the theater. 

When we have sufficient information available from a more intensive survey, all 
of those data can be analyzed to tell what is the polar characteristic of the screen. 
While the indications are not definite, yet they tend to show that the screens all 
were matte and had a fairly uniform reflectivity within the angles encountered in 
the particular theaters surveyed. 

MR. SCHLANGER: What brightness is best for different density conditions of 
film or what lambert will produce the best contrast value for discerning image 
detail? The light values alone will not give us the ultimate answer unless we have 
tests made with actual film strips. 

MR. ZAVESKY: That point is realized by the committee, but the committee 


chose to consider first things first. One of the basic unknowns was the present 
value. Once that is determined, our activity can be enlarged to include such very 
pertinent questions as you have raised. 

MR. SCHLANGER: Will not that affect the recommended foot-lambert measure- 

MR. ZAVESKY: It probably will if it is demonstrated by proper tests that the 
standards should be changed. Right now the standards are 9 to 14 foot-lamberts. 

MR. GEORGE LEWIN : Could you give us a little more detail as to the type of 
instrument with which you measured the brightness? 

MR. ZAVESKY: That was a Luckiesh-Taylor visual photometer. 

MR. LEWIN: I am not familiar with that. Can you tell definitely what part 
of the screen you are looking at when you look through the instrument? Is it a 
focused image? 

MR. ZAVESKY: You can use either a view finder which we did in some in- 
stances or by locating on the screen, at the same time some one is measuring 
illumination with a photronic cell, it is possible to tell where you are on the screen 
and knowing the angle of acceptance of ther instrument and the distance you are, 
you can tell what portion of the screen you are actually measuring when you are 
measuring brightness. 

MR. LEWIN: I assume, then, you did not use the Weston instrument that is 
available to a limited extent right now? 

MR. ZAVESKY: For measuring brightness? 

MR. LEWIN: Yes. 

MR. ZAVESKY: I am not familiar with that one. 

MR. LEWIN : It is a foot-lambert meter which has been put out on a small scale. 

MR. N. D. GOLDEN: Based upon your findings that you projected on the 
screen there, the wide variance of percentages that you have found as conditions 
exist in different theaters, would you not come to the conclusion that possibly a 
great deal of the fault is based upon the poor quality or outmoded use of the 
screens and possibly the projection equipment used in the theaters that you 

MR. ZAVESKY: I do not think the Committee has done enough to take any 
stand at all on that, Mr. Golden. 

MR. GOLDEN: Because of the wide variance in your percentages found in 
some cases your results were of a higher degree and in a great many cases they 
were of low degree you can, therefore, come to but one conclusion : Either the 
screens were old, dirty, and outmoded, or the light sources projected from the 
projection room were not adequate. 

MR. ZAVESKY: Certainly if you are investigating the basic reasons for those 
things which were discovered, you have two factors to consider: what light is 
projected to the screen and what is reflected. So that on a very broad generali- 
zation the reasons why the brightness was not up or why the light intensity was 
not what it might have been have to be attributed to one or the other. That was 
not determined in this survey. 

MR. GOLDEN: I quite understand that, but I think it would be the object of 
your Committee to find out whether or not the equipment in use in the theaters of 
the country, screens, projection equipment, light sources, and everything in- 
volved needs replacing and can very well stand it. 


MB. ZAVESKY: Your suggestion will certainly be, given consideration by the 
committee, Mr. Golden. 

MR. JOHN H. KURLANDER : One of the items measured there was the projection 
distance. I noticed that the projection distance was measured from the aperture 
to the screen. Now I have always considered that the projection distance was 
measured from the front surface of the lens nearest the screen to the screen itself. 
The projection lens constitutes the last light source in the train. It is true that 
the screen there is rather small. However, inasmuch as the foot-candles on the 
screen are determined absolutely by the brightness of the lens and the lens area, 
the effective lens area and that varies inversely as the square of the distance 
that discrepancy becomes somewhat larger. Why was the distance chosen as 
being from the aperture to the screen? 

MR. ZAVESKY: It is more a question of saying that it was from the aperture to 
the screen. rather than a specific measurement. The determination of that dis- 
tance was made by measuring from the screen to the point in the theater on a 
parallel under which we estimated the projector to be, and then calculating from 
the projection angle what the actual distance was. 

I am quite sure that those figures are not accurate to better than 6 inches, but 
even considering the shortest throw, a 65-foot throw, an error of plus or minus 6 
inches, will be not more than 1 per cent. * 

MR. KURLANDER: I brought thatlip merely for the sake of accuracy because 
the projection distance is actually measured from the last lens in the system, and 
that is the projection lens to the screen. 

The second point is with regard to the relatively low values of reflection factors 
for these screens. Was that reflection factor determined on the basis of an inte- 
grated effect over an appreciable area of the screen which took into account the 
screen perforations or was that intended to represent the coefficient of reflection of 
the screen surface itself, that is, the reflecting efficiency of the screen surface? 

MR. ZAVESKY: That was determined by taking the ratio of the brightness 
measured at the center of 'the screen to the -light intensity at the center of the 
screen. The brightness-measuring instrument probably did not include more 
than an area of 1 to 2 square feet. It certainly took into consideration if tnere 
were holes in the screen as it existed in the theater at the center. 

MR. KURLANDER: It was an integrated effect? 

MR. ZAVESKY: For a small area at the center of the screen. 

MR. KURLANDER: There again the actual coefficient of the reflection of the 
screen surface would be higher than is shown. 

MR. ZAVESKY: You mean of the unperf orated screen? 

MR. KURLANDER: That is right. 

MR. ZAVESKY: I expect it would be. 

Report of ASA Committee on 
Standards for Motion Pictures, Z22 

DURING THE YEAR 1947, fourteen American Standards on motion 
pictures were approved. Of these, the following three were re- 
affirmed from previous Z22 standards with only editorial changes : 

Z22. 10-1947 Emulsion Position in Projector for Direct Front Projection of 16- 

^ Millimeter Silent Motion Picture Film 

Z22. 16-1947 Emulsion and Sound-Record Positions in Projector for Direct 

Front Projection of 16-Millimeter Sound Motion Picture Film 
Z22. 22-1947 Emulsion Position in Projector for Direct Front Projection of 8- 

Millimeter Silent Motion Picture Film 

Although the two 16-millimet'er emulsion-position standards (Z22.10 
and Z22.16) were unanimously reaffirmed with only editorial changes, 
reconsideration was subsequently requested by Mr. K. F. Abeel, rep- 
resenting the General Electric Company. Since several other mem- 
bers who had voted for reaffirmatio'n joined Mr. Abeel in asking for 
reconsideration, the chairman appointed the following subcommittee 
to prepare a further analysis of 16-millimeter photographing and 
printing practices for consideration of the entire Committee : A. W. 
Cook, chairman, K. F. Abeel, M. C. Batsel, 0. Sandvik, and E. 

The four following standards were reconsidered and modified in 
their methods of dimensioning, to be more useful in actual practice : 

Z22.5 Cutting and Perforating Dimensions for 16-Millimeter Silent Motion 

Picture Negative and Positive Raw Stock 
Z22.12 Cutting and Perforating Dimensions for 16-Millimeter Sound Motion 

Picture Negative and Positive Raw Stock 
Z22.17 Cutting and Perforating Dimensions for 8-Millimeter Motion Picture 

Negative and Positive Raw Stock 
Z22.36 Cutting and Perforating Dimensions for 35-Millimeter Motion Picture 

Positive Raw Stock 

The principal changes in the above standards consisted in showing di- 
mensions as measured from the edges of sprocket holes rather than 
from center lines. 

In reviewing the 35-Millimeter Projector-Sprocket Specification, it 
was found desirable to make a further study of the sprocket diameter, 
which had been standard since 1930. In the reapproved edition, 
Z22.35-1947, 16-Tgoth 35-Millimeter Motion Picture Projector 


Sprockets, this dimension has been changed to 0.943 inch (from 0.945 
inch) to reduce film wear. 

The Standard for Photographic Density Z22.27 was revised to take 
advantage of the more detailed standard developed for Still Photog- 
raphy Z38.2.5-1946. 

Two new standards on camera and projector apertures were based 
on corresponding Z52 War Standards : 

Z22. 59-1947 Photographing Aperture of 35-Millimeter Sound Motion Picture 

Z22 . 58-1947 Picture-Projection Aperture of 35-Millimeter Sound Motion Picture 


Film-Nomenclature Standard Z22.56-1947 and 16-Millimeter Buzz- 
Track Test Film Z22.57-1947 were also taken from Z52 War Stand- 
ards without change. The new standard Z22. 55-1947, 35-Millimeter 
Sound Motion Picture Release Prints, is essentially a statement of cur- 
rent American practice in the preparation of 35-millimeter motion 
picture film in 2000-foot lengths for distribution to theaters. 

Shortly after the Screen-Size Standard Z22.29-1946 was adopted, 
the objection was raised that it was not clear as to whether or not the 
dimensions included the entire screen or only the useful area. Conse- 
quently the Chairman asked the Motion Picture Research Council to 
make a proposal for revision which would clarify this point. 

The following nine proposed standards on 35-millimeter test films 
were prepared by the Motion Picture Research Council and sub- 
mitted by letter ballot to members of the Z22 Committee : 

Z22.60 Theater Sound Test Film for 35-Millimeter Motion Picture Sound- 
Reproducing Systems 

Z22.61 Service-Type Sound-Focusing Test Film for 35-Millimeter Motion Pic- 
ture Sound Reproducers 

Z22.62 Laboratory-Type Sound-Focusing Test Film for 35-Millimeter Motion 
Picture Sound Reproducers 

Z22 . 63 Service-Type Multifrequency Test Film for 35-Millimeter Motion Pic- 
ture Sound Reproducers 

Z22.64 Laboratory-Type Multifrequency Test Film for 35-Millimeter Motion 
Picture Sound Reproducers 

Z22.65 Service-Type Scanning-Beam Uniformity Test Film for 35-Millimeter 
Motion Picture Sound Reproducers 

Z22.66 Laboratory-Type Scanning-Beam Uniformity Test Film for 35-Milli- 
meter Motion Picture Sound Reproducers 

Z22 . 67 1000-Cycle Balancing Test Film for 35-Millimeter Motioru Picture 
Sound Reproducers 


Z22 . 68 Buzz-Track Test Film for 35-Millimeter Motion Picture Sound Repro- 

Each of these proposals covers a test film which is now in general use. 

Two proposed standards for dimensions of 200-mil push-pull sound 
tracks were also submitted by the Motion Picture Research Council. 
Since these proposals, did not include tolerances, the Chairman ap- 
pointed the following Committee to prepare revised proposals conform- 
ing to other sound track standards: G. R. Crane, chairman, M. C. 
Batsel, W. F. Kelly, L. L. Ryder, and W. C. Miller. 

The following 15 standards were referred to the Society of Motion 
Picture Engineers for revision on November 5, 1945 : 

Z22 . 7-1941 Camera Aperture for 16-Millimeter Silent Motion Picture Film 
Z22 . 8-1941 Projector Aperture for 16-Millimeter Silent Motion Picture Film 
Z22 . 13-1941 Camera Aperture for 16-Millimeter Sound Motion Picture Film 
Z22 . 14-1941 Projector Aperture for 16-Millimeter Sound Motion Picture Film 
Z22 . 19-1941 Camera Aperture for 8-Millimeter Silent Motion Picture Film 
Z22 . 20-1941 Projector Aperture for 8-Millimeter Silent Motion Picture Film 
Z22 . 34-1930 Cutting and Perforating Negative and Positive Raw Stock for 35- 
Millimeter Motion Picture Film 

Z22 .4-1941 Projection Reels for 35-Millimeter Motion Picture Film 
Z22 . 1 1-1941 Projection Reels for 16-Millimeter Motion Picture Film 
Z22 . 23-1941 Projection Reels for 8-Millimeter Silent Motion Picture Film 
Z22 . 26-1941 Sensitometry for Motion Picture Film 
Z22 . 24-1941 Film Splices Negative and Positive for 16-Millimeter Silent Motion 

Picture Film 
Z22 . 25-1941 Film Splices Negative and Positive for 16- Millimeter Sound Motion 

Picture Film 

Z22 . 6-1941 Projector Sprockets for 16-Millimeter Motion Picture Film 
Z22 . 18-1941 8-Tooth Projector Sprockets for 8-Millimeter Motion Picture Film 

It is hoped that the Society will submit recommendations for revision 
of these standards at an early date. 

At the request of Eastman Kodak Company, War Standards Z52.51- 
1946 Base Point for Distance Scales 16-Millimeter Cameras and 
Z52.50-1946 Lens-Registration Distance 16-Millimeter Cameras were 
referred to .the Society of Motion Picture Engineers on February 4, 
1947, for recommendations for American Standards. 

Fader Setting Instructions Z22. 32-1941 was unanimously with- 
drawn since the practice described is no longer followed. 

The attention of the Committee was drawn to the apparent omis- 
sion of silent pictures from the Scope as originally adopted. Since 
this w^s, of course, unintentional the following revision of the Scope 
was proposed and adopted : 


The formulation of definitions, dimensional standards, methods 
of test and rating, and performance characteristics of materials 
and devices used in silent and sound motion picture photography 
and in sound recording, processing, and reproduction in connec- 
tion therewith. 

The revised Scope has been submitted to the International Standards 
Organization for its approval as the Scope for the international proj- 
ect. In this connection it will be recalled that the American Stand- 
ards Association has been designated as the Secretariat of Motion 
Picture Standards for the ISO. All ASA standards on motion pictures 
will be submitted to the ISO for consideration. 

The chairman wishes to express his appreciation for the active co- 
operation of the Society of Motion Picture Engineers, Motion Picture 
Research Council, and members of the Z22 Committee. 


ALFRED N. GOLDSMITH, Honorary Chairman 
W. H. DEACY, JR., Secretary 

Acoustical Society of America F. L. HOPPER 

American Society of Cinematographei s JOSEPH RUTTENBERG 

Ansco Division of General Aniline and Film 

Corporation ALAN W. COOK 

ASA Sectional Committee on Standardiza- 
tion in the Field of Pliotography, Z38 L. A. JONES 

Bausch and Lomb Optical Company K. PESTRECOV 

(Alternate) L. V. FOSTER 

Bell and Howell Company M. G. TOWNSLEY 

The Calvin Company LLOYD THOMPSON 

(Alternate) F. O. CALVIN 

De Luxe Laboratories E. A. BERTRAM 

(Alternate) F. G. GRIGNON 

E. I. du Pont de Nemours and Company. .J. E. SCHMIDT 
Eastman Kodak Company O. SANDVIK 

(Alternate) M. E. RUSSELL 

Illuminating Engineering Society RALPH E. FARNHAM 

International Projector Corporation H. BARNETT 

J. A. Maurer, Inc J. A. MAURER 

(Alternate) R. C. HOLSLAG 

Mitchell Camera Corporation G. A. MITCHELL 

Motion Picture Association of America J. B. McCuLLOUGH 



National Bureau of Standards RAYMOND DAVIS 

National Carbon Company D. B. JOY 

(Alternate) F. T. BOWDITCH 

General Electric Company ' K. F. ABBEL 

Optical Society of America A. C. HARDY 

Photographic Society of America ALLEN STIMSON 

(Alternate) WILLIAM YALE 

Radio Corporation of America, RCA Victor 

Division M. C. BATSEL 

(Alternate) R. O. DREW 

Motion Picture Research Council FARCIOT EDOUART 


Society of Motion Picture Engineers F. T. BOWDITCH 


(Alternate) D. F. LYMAN 

Technicolor Motion Picture Corporation JOHN R. CLARK, JR. 

United States Navy Department E. S. COBB 

United States War Department, Army Air 

Forces C. B. KRUMM 

(Alternate) R. D. FULLERTON 

United States War Department, Medical 


United States War Department, Signal 


(Alternate) E. P. SUTHERLAND 

Western Electric Company G. R. CRANE 

Member-at-Large ALFRED N. GOLDSMITH 

SMPE American Standards 


American Standards on 
Motion Pictures 

This is a review of all current American Standards in the Z22 series and 
others of interest to the motion picture industry that have been approved and 
published by the American Standards Association. 

SINCE THE SMPE, the Motion Picture Research Council, and the 
American Standards Association began active work on their en- 
larged motion picture standards program in January, 1946, 40 perti- 
nent motion picture standards have been approved and published. 
They have all been considered by engineering committees of the So- 
ciety at some time in the history of their development, and were rec- 
ommended for adoption by the SMPE Standards Committee. Some 
are revisions of previous issues that were recently brought up to date, 
others are modifications of Z52 War Standards that the motion pic- 
ture industry requested be carried over in permanent form, while one 
is a Z38 Photography Standard that is referred to here because it is of 
importance to motion pictures. 

All 40 standards are available in 8y 2 - X 11-inch format, punched 
to fit the standard three-ring binder. These standards are published 
also in the JOURNAL for the information of members, as soon after 
ASA approval as possible. Usually a report accompanies the new 
standard giving the history of its development, with a statement of 
the reasons for adopting certain dimensions or methods of presenta- 
tion where these things might not be readily apparent. 

The issues of the JOURNAL for April and September, 1946, August 
and December, 1947, and the current issue carry 39 of the 40 stand- 
ards listed below, the other being the Z38 Standard that is described 
but will not be published. 

All persons who purchased the SMPE American Standards Binjder 
shown on page 278, from the Society, are notified each time new stand- 
ards are approved so that they may keep their records always up to 
date. The name and address of the original purchaser are kept on 
a stencil by the Society, making notification automatic, where the 
original purchaser still has his binder. However, many binders have 
since changed hands without a change of stencil, so undoubtedly a 
number of incomplete records are now in use. If you are not certain 
that you have all 40, be sure to check what you do have against this list. 




The last of these notices, which was mailed out in October, 1947, 
listed the 14 standards in the following list that are followed by an as- 
terisk. If they are missing from your set, please notify Boyce Nemec, 
Executive Secretary, so that your name arid correct address can be 
placed on the list for future notices. There is no charge for this serv- 
ice, but there is a charge for the standards, which are available in 
sets only from the Society, or as individual copies from the American 
Standards Association, 70 East 45th Street, New York 17, N. Y. The 
last group of 14 standards may be purchased from the Society for 
$2.30, representing a substantial saving over the single copy price. 

The Society also has a small stock of complete sets of 40 standards 
with binders available for $7.40, when mailed to an address in the 
United States, or for $7.90 when mailed to a foreign country. Your 
order automatically will put your name on the mailing list, so be cer- 
tain to show the correct name and address of the person who will use 
the standards, and not just the name of your company or purchasing 

Z22. 2-1946 

Emulsion and Sound-Record Positions in Camera for 35-Milli- 
meter Sound Film 

Emulsion and Sound-Record Positions in Projector for 35-Milli- 
meter Sound Film 

Cutting and Perforating Dimensions for 16-Millimeter Silent 
Negative and Positive Raw Stock 

Emulsion Position in Camera for 16-Millimeter Silent Film 
Emulsion Position in Projector for 16-Millimeter Silent Film 
Cutting and Perforating Dimensions for 16-Millimeter Sound 
Negative and Positive Raw Stock 

Emulsion and Sound-Record Positions in. Camera for 16-Milli- 
meter Sound Film 

Emulsion and Sound-Record Positions in Projector for 16-Milli- 
meter Sound Film 

Cutting and Perforating Dimensions for 8-Millimeter Negative 
and Positive Raw Stock 

Emulsion Position in Camera for 8-Millimeter Silent Film 
Emulsion Position in Projector for 8-Millimeter Silent Film 
Method of Determining Transmission Density of Films 
(includes Z38. 2. 5-1946 Diffuse Transmission Density) 

Z22. 28-1946 Dimensions for Projection Rooms and Lenses for Theaters 
Dimensions for Theater Projection Screens 
Definition for Safety Film 

Dimensions for 16-Tooth 35-Millimeter Projector Sprockets 
Cutting and Perforating Dimensions for 35-Millimeter Positive 
Raw Stock 

Z22 .37-1944 Raw-Stock Cores for 35-Millimeter Film 

Z22. 3-1946 

Z22. 10-1947* 
Z22. 12-1947* 

Z22. 15-1946 
Z22. 16-1947* 
Z22. 17-1947* 

Z22. 21-1946 
Z22. 22-1947* 
Z22. 27-1947* 

Z22. 29-1946 
Z22. 31-1946 
Z22. 35-1947* 
Z22. 36-1947* 




Z22. 38-1944 Raw-Stock Cores for 16-Millimeter Film 

Z22 . 39-1944 Screen Brightness for 35-Millimeter Motion Pictures 

Z22. 40-1946 Sound Records and Scanning Area of 35-Millimeter Sound Prints 

Z22. 41-1946 Sound Records and Scanning Area of 16-Millimeter Sound Prints 

Z22. 42-1946 Specifications for Sound-Focusing Test Films for 16-Millimeter 
Sound-Projection Equipment 

Z22 . 43-1946 Specifications for 3000-Cycle Flutter Test Film for 16-Millimeter 
Sound Projectors 

Z22. 44-1946 Specifications for Multifrequency Test Film for Field-Testing 16- 
Millimeter Sound-Projection Equipment 

Z22. 45-1946 Specifications for 400-Cycle Signal-Level Test Film for 16-Milli- 
meter Sound-Projection Equipment 

Z22.46-1946 16-Millimeter Positive Aperture Dimensions and Image Size for 
Positive Prints Made from 35-Millimeter Negatives 

Z22. 47-1946 Negative Aperture Dimensions and Image Size for 16-Millimeter 
Duplicate Negatives Made from 35-Millimeter Positive Prints 

Z22. 48-1946 Printer- Aperture Dimensions for Contact Printing 16-Millimeter 
Positive Prints from 16-Millimeter Negatives 

Z22.49-1946 Printer- Aperture Dimensions for Contact-Printing 16-Millimeter 
Reversal and Color-Reversal Duplicate Prints 

Z22 . 50-1946 Reel Spindles for 16-Millimeter Projectors 

Z22. 51-1946 Method of Making Intermodulation Tests on Variable-Density 
16-Millimeter Sound Prints 

Z22. 52-1946 Method of Making Cross-Modulation Tests on Variable-Area 16- 
Millimeter Sound Prints 

Z22. 53-1946 Method of Determining Resolving Power of 16-Millimeter Pro- 
jector Lenses 

Z22. 54-1946 Method of Determining Freedom from Travel Ghost in 16- 
Millimeter Sound Projectors 

Z22. 55-1947* 35-Millimeter Sound Motion Picture Release Prints in Standard 
2000-Foot Lengths 

Z22. 56-1947* Nomenclature for Motion Picture Film Used in Studios and 
Processing Laboratories 

Z22 . 58-1947* Picture-Projection Aperture of 35-Millimeter Sound Projectors 

Z22 . 59-1947* Photographing Aperture of 35-Millimeter Sound Cameras 

Z38. 3. 1-1943* Definition of Safety Photographic Film 

There is no standard numbered Z22.1, and Z22.32 has been can- 
celed, leaving eighteen intervening yet to come and of these, 
Z22 . 57-1947 Specifications for 16-Millimeter Buzz Track Test Film 

will appear in a later issue of the JOURNAL with a review of its recent 
past history. 

The remaining seventeen standards are in various stages of develop- 
ment, in Committees of the Society, the Motion Picture Research 
Council, or in Subcommittees of Z22, the ASA Committee on Motion 

Five Recent American Standards 
on Motion Pictures 

The Standards shown or described here are the last five of a series of forty 
American Standards of interest to motion picture engineers that are listed 
in a short review article beginning on page 279 of this issue. 

Density of Motion Picture Films 

THE AMERICAN STANDARD Z22.27-1947, a revised version of a simi- 
lar standard that appeared on page 245 of the JOURNAL for 
March, 1941, indicates that the motion picture industry has adopted 
the diffuse visual and printing density standards defined in another 
American Standard, Z38.2. 5-1946, Diffuse Transmission Density. 
Prepared by the ASA Committee on Photography, with concurrence 
from the SMPE Standards Subcommittee on Sensitometry and 
Density, the Z38 document is an excellent treatise on the subject. 
Apparatus and procedures for evaluating the diffuse transmission 
density of photographic materials by integrating-sphere, opal-glass, 
and contact-printing methods are described. Outline diagrams of 
several types of instruments accompany each description, making 
it easy to visualize their fundamental differences as well as physi- 
cal arrangement and operation. 

With this standard it becomes practicable to calibrate a number 
of photographic samples to use as reference specimens for calibrat- 
ing 'ordinary densitometers. 

In general. only densitometers which conform to the conditions 
specified are capable of giving accurate readings of American Stand- 
ard diffuse visual or printing density for all types of photographic 
materials. However, many simple densitometers give readings on 
different materials with sufficient accuracy for most practical work. 

If a nonconforming densitometer is to be used in connection with 
a given type of photographic material, it may be calibrated from 
reference samples composed of the same material. In this way any 
type of densitometer can be calibrated to read " American Standard 
diffuse visual or diffuse printing density" on any single type of photo- 
graphic material, to a degree of accuracy commensurate with the sta- 
bility and reproducibility of the instrument itself. 


. 283 

American Standard 

Method of Determining Transmission 
Density of Motion Picture Films 

Reg. U. S. Pal. Og. 


Revision of 


The method of determining transmission density of motion picture films 
shall be in accordance with the American Standard for Diffuse Transmission 
Density, Z38.2.5-1946. Whe're applicable, either diffuse visual density, Type 
VI -b, or diffuse printing density Type P2-b, shall be used. 


Release Prints in 2000-Foot Lengths 

American Standard Z22. 55-1947 specifies the length and detailed 
makeup of head and tail leaders for 35-mm release prints customarily 
mounted on 2000-foot reels. This is the first time such information 
has appeared as a formal American Standard but it has been an 
"Academy Standard" used in substantially the same form for many 

Because of vast quantities of release material that had been ex- 
changed between Great Britain and the United States, the British 
hoped that the standards of both nations could be made alike in all 
respects, so the British Standards Institution transmitted their rec- 
ommendations on the subject to the Research Council in March, 
1945, requesting American consideration of their proposed standards. 
These were considered at a joint meeting of the Society of Motion 
Picture Engineers and the Research Council in May, 1945, when 
several modifications were incorporated in the proposed American 
Standard which was later submitted to Z22, the ASA Committee on 
Motion Pictures for approval. 

During the Z22 balloting, Mr. John R. Clark, representing the 
Technicolor Motion Picture Corporation, suggested a modification in 
the terminology formerly used. He was. opposed to the use of the 
word trailer since in the experience of the American motion picture 
industry the word trailer had come to refer only to the preliminary ad- 
vertising films which are exhibited in advance of the feature. He sug- 
gested that the word leader might be substituted and all members of 
Z22 agreed, recommending that it appear in the standard as head 
leader and tail leader because the meanings would be easily under- 
stood by anyone familiar with commercial motion picture practice. 
The standard was subsequently validated in its approved form by the 
Standards Council of the ASA on September 29, 1947. 

The standard specifies the size and location of change-over cue 
marks and states that the motor cue shall be circular opaque marks 
with a transparent outline printed from the negative. It is customary 
to use a serrated die for making these marks; however an alternate 
procedure of marking with ink is described. 



35-Mm Camera and Projector Apertures 

American Standards Z22.58 and Z22.59, specifying apertures for 
35-mm cameras and projectors, are identical with two American 
War Standards (Z52.37 and Z52.36) published in 1944 for the 
Army and Navy. Although not previously dignified as American 
Standards, these apertures have been in common use since shortly 
after the advent of sound motion pictures. 

During the transition from silent to sound films there was a great 
deal of confusion about the amount of picture that would appear 
on the release print, so as a temporary measure the Society recom- 
mended that the cameraman compose the 'picture within the limits of 
a rectangle 0.620 by 0.835 inch. Projection apertures at the same 
time were recommended as 0.600 by 0.800 inch, which gave a three- 
to-four, height-to- width ratio. In spite of camera and projector aper- 
tures being, two of the most vital interchangeability elements in 
motion pictures they have had a rather hectic history. 

There was a 35-mm silent SMPE Standard Motion Picture Aper- 
ture 0.6795 by 0.9060 inch, adopted in 1922 with a recommendation 
that it be titled Projector Aperture. After three years of discussion 
in this country, England, and France, the Society announced pro- 
posed dimensions for the three apertures in 1925 as 

Camera 0.700 by 0.925 inch 

Printer. 0.757 by 1.000 inch 

Projector 0.725 by 0.950 inch 

They were mentioned on page 411 of The Transactions of the Society 
for August, 1927, where it was pointed out that the 1922 Standard 
was then still in effect and that since during the five-year period no 
projector apertures had been changed to agree with the new proposal, 
probably none would be, so no further action was taken to obtain ap- 
proval of any of the 1925 proposals. 

Subsequently, in 1934, the interim Sound-Projector Aperture 
(0.620 by 0.835 inch) was replaced by an SMPE Standard that agrees 
with the new American Standard shown here and which was accom- 
panied by an SMPE Camera-Aperture Standard that also is in agree- 
ment with the new Camera-Aperture Standard published in this issue. 




American Standard 

Picture Projection Aperture of 35-Millimeter 
Sound Motion Picture Projectors 

Kff. v. s. pai. og. 












A J 










F ; 








0.825 0.002 

20.95 0.05 


0.600 0.002 

15.25 0.05 


0.738 0.002 

18.74 0.05 

















0.05 approx 

1.3 approx 

a = b = '/a longitudinal perforation pitch. 

These dimensions and locations are shown relative 
to unshrunk raw stock. 

Nofe.- The aperture dimensions given result in a screen pic- 
ture having a height-to-width ratio of 3 to 4 when the projection 
angle is 14 degrees. 





American Standard 

Photographing Aperture of 35-Millimeter 
Sound Motion Picture Cameras 

R.-S. V S. Pa'. Og. 






h F l 


























- ^ \ 








0.868 0.002 
0.631 0.002 
0.744 0.002 
0.03 approx 

22.05 0.05 
16.03 0.05 
18.90 0.05 
0.8 approx 

a = b !/2 longitudinal perforation pitch. 

These dimensions and locations are shown relative 
to unshrunk raw stock. 

Note: The aperture dimensions given in combination with 
an 0.600 X 0.825 in. (15.25 X 20.95 mm) projector aperture 
result in a screen picture having a height-to-width ratio of 
3 to 4 when the projection angle is 14 degrees. 


Definition of Safety Film 

The American Standard Definition of Safety Photographic Film 
Z38. 3. 1-1943 defines a photographic film which is no more hazardous 
than common newsprint paper. In order to be classified as Safety 
Photographic Film, a photographic film must (a) be difficult to ignite, 
(b) be slow burning, and (c) evolve a limited amount of toxic oxides of 
nitrogen during decomposition. 

The ease of ignition is determined by measuring the time of ignition 
after subjecting the sample to a uniformly maintained high tempera- 
ture. The requirement for ease of ignition and the test method are the 
same as those specified by the British Standard Definition of Cinemat- 
ograph "Safety" Film (1939) and other European standards for 
safety motion picture film. 

The rapidity of burning and the method of measuring that charac- 
teristic are also the same as specified in the British Standard Definition 
of "Safety" Film (1939). 

The toxic gases evolved when photographic films of cellulose nitrate 
are decomposed by heat are oxides of nitrogen, carbon monoxide, and 
hydrocyanic acid. Laboratory tests made available to the committee 
indicate that only oxides of nitrogen and carbon monoxide are evolved 
in sufficient quantities to constitute an appreciable hazard. These 
tests also indicate that photographic film does not evolve more car- 
bon monoxide than does common newsprint paper when equal quan- 
tities of film and paper are decomposed in the same manner. 

The maximum quantity of oxides of nitrogen which can evolve 
when safety photographic film decomposes is limited by stipulating in 
the definition the maximum nitrogen (present as nitrate) content of 
the material. Fumes from photographic film that comply with this 
standard will not be significantly different from fumes evolved from 
ordinary newsprint paper decomposed under the same conditions. 

Photographic films made from materials for which this definition 
applies but which do not comply in one or more respects are not nec- 
essarily hazardous. For example, acetate film may fail to comply 
with the maximum nitrogen content specified in this definition and 
still not be significantly more hazardous than common newsprint pa- 
per under ordinary conditions. 

The committee considered a maximum nitrogen content of 0.72 per 
cent and had some evidence that a safety film containing that propor- 
tion of nitrogen was no more toxic than films with a lower content. 


However, the specification was set at a lower figure to correspond with 
the current requirements of the Underwriters' Laboratories. The 
method for measuring the nitrogen content was adopted from the 
Summary of Requirements for Slow Burning Cellulose Acetate Film, 
Underwriters' Laboratories, Inc., Chicago, Illinois. 

The definition of Safety Photographic Film applies only to films, 
the supports for which comprise cellulose esters of simple fatty acids, 
combinations of cellulose esters and nitrate, and regenerated cellu- 
lose. Should photographic films in the future be made of other ma- 
terials, this definition may have to be modified and additional re- 
quirements incorporated in the definition, which now specifies ignition 
time and burning time, outlines in detail the methods for measuring 
these two characteristics, and, in addition, presents a standardized 
procedure for determining nitrogen content of film samples. 

This standard, a 6-page pamphlet, was supplied by the SMPE with 
the last set of fourteen standards furnished to Binder subscribers and 
is now also available in single copy form from the American Standards 
Association, 70 East 45th Street, New York 17, N. Y. 

29 TEST FILMS, both 16- and 35-Mm are produced jointly by 
the SMPE and Motion Picture Research Council. Write for 
complete catalog. 

40 AMERICAN STANDARDS on Motion Pictures are available. 
See page 279 of this issue for details. 

MAGNETIC RECORDING reprints of six important papers pub- 
lished in the Journal in January, 1947, may be purchased 
from the SMPE for 75 cents. 

MEMBERSHIP CERTIFICATES 111/2 by 14 inches with your name 
hand engrossed and suitable for framing may be purchased 
from the SMPE for $1.50. 



was born in Illinois on No- 
vember 15, 1892. Appointed to 
the Regular Army from Iowa, 
he served in both the Infantry 
and the Signal Corps. He re- 
tired on July 31, 1947, for physi- 
cal disability incurred in line of 
duty, and died on September 11, 
1947, in New York City. 

In 1932-1933 Colonel Gillette 
pursued a course of instruction 
in motion picture production in 
Hollywood, under the auspices 
of the Research Council of the 
Academy of Motion Picture 
Arts and Sciences. Following 
this he was assigned as Officer 
in Charge of the Signal Corps 
Photographic Laboratory at the 
Army War College. 

In August, 1935, he joined 
the Society of Motion Picture 
Engineers as an Active Member 
and later was elevated to the 
Fellow grade. Despite a heavy 
load of Army administrative and 
other duties, he wrote two papers for the JOURNAL both of which 
dealt with the use of films in military training. In 1936 he pre- 
pared the Army directive outlining the scope and function of the 
training film, and later saw the pattern that he had prescribed used 
by all American Arms and Services. 

In March of 1942 Colonel Gillette was assigned as Commanding 
Officer of the Signal Corps Photographic Center, then established 
in the former Paramount Studios at Astoria. Here his constant 
effort and organizing ability were responsible for the successful 
establishment of what became the largest government-operated 
motion picture studio in the world. 

During World War II he served in the Mediterranean Theater 
as Photographic Officer to General Mark W. Clark, and later as 
Photographic Officer and Signal Officer in the Mid-Pacific. For 
his distinguished service Colonel Gillette was awarded the Legion 
of Merit and the Bronze Star Medal. He was a man of tremendous 
energy and had an intensity and sincerity of purpose and a devotion 
to duty that no one could fail to admire. 

Corps Photograph 


63rd Semiannual Convention 


Ambassador Hotel Del Mar Beach Club 
Santa Monica, California May 17-21, 1948 


LOREN L. RYDER. President 

DONALD E. HYNDMAN .Past-President 

EARL I. SPONABLE Executive Vice-President 

JOHN A. MAURER Engineering Vice-President 

CLYDE R. KEITH Editorial Vice-President 

JAMES FRANK, JR Financial Vice-President 

WILLIAM C. KUNZMANN. Convention Vice-President 

G. T. LORANCE Secretary 


Geiieral Office, New York 

BOYCE NEMEC ' Executive Secretary 

THOMAS F. Lo GIUDICE , Staff Engineer 

MARGARET C. KELLY * . . . . Offic9 Manager 

HELEN M. .STOTE Journal Editor 


S. P. Solow 


G. A. Chambers, Chairman 
N. L. Simmons, Jr., Vice-Chairman, West Coast 


Harold Desfor, Chairman 
S. D. Spangler, Vice-Chairman, West Coast 

W. C. Kunzmann, Chairman 
Assisted by C. W. Handley, L. H. Walters, and W. Farley, Jr. 


G. F. Rackett, Chairman Mrs. S. P. Solow, Hostess 


Watson Jones, Chairman G. C. Misener, Chairman, West Coast 


R. H. McCullough, Chairman 
Lloyd C. Ownbey, Vice-Chairman 

Assisted by officers and members Los Angeles Projectionist's Local 150 

W. J. Colleran, Chairman P. E. Brigandi, Chairman 




Monday, May 17 

9:30 A.M. Registration, Sixth Floor, Santa Monica Ambassador Hotel 

Advance Sale of Luncheon and Banquet Tickets 
11:00 A.M. Business Session, Magnolia Room, Ambassador Hotel 
12:30 P.M. Luncheon, Ocean Room, Del Mar Beach Club 

2 : 00 P.M. Technical Session, Magnolia Room 

8:00 P.M. Technical Session, Magnolia Room 

Tuesday, May 18 

10:00 A.M. Registration, Sixth Floor, Ambassador Hotel 

Advance Sale of Banquet Tickets 
2 : 00 P.M. Technical Session, Magnolia Room 
8:00 P.M. Technical Session, Magnolia Room 

Wednesday, May 19 

9 : 30 A.M. Registration, Sixth Floor, Ambassador Hotel 

Advance Sale of Banquet Tickets 

10:30 A.M. Demonstration by Thorobred Photo Service, Inc., Hollywood Park 
Race Track 


NOTE: Registration headquarters will be open this afternoon until 3:00 P.M. 
to those desiring banquet tickets and making table reservations. 

7: 15 P.M.-8:15 P.M. Cocktail Hour for holders of banquet tickets, Rouge 
Room, Ambassador Hotel 

8: 30 P.M. 63rd Semiannual Banquet (dress optional), Magnolia Room, Am- 
bassador Hotel. Entertainment and dancing 

Thursday, May 20 

2 : 00 P.M. Technical Session, Magnolia Room 

Joint Meeting with Inter-Society Color Council 

"Light Sources," by Norman MacBeth, Consulting Engineer 

"The Effect of Light Sources on Colored Objects," by E. I. Stearns, 

Calco Company 
"The Color Range of a Three-Color Subtractive System," by Carl 

E. Foss, Inter-Society Color Council 

"How the Eye Works," by I. A. Balinkin, University of Cincinanti 
8 : 00 P.M. Technical Session, Magnolia Room 

Joint Meeting with Inter-Society Color Council 
"An Introduction to Color," by Ralph Evans, Eastman Kodak 




2:00 P.M. 

8: 00 P.M. 

Friday, May 21 


Technical Session, Magnolia Room 

"Masking in Color Duplication," by Thomas Miller, Eastman Kodak 

"Principles and Practice of Three-Color Subtractive Photography," 
by W. T. Hanson and F. Richey, Eastman Kodak Company 

"Make-up for Color Photography," by Hal King, Max Factor 

"Two-Color Photography," by Thomas Gavey, University of 
Southern California 

Technical Session and Adjournment of the 63rd Semiannual Conven- 
tion, Magnolia Room 

The following additional papers have been tentatively scheduled, but the 
definite times of their delivery have not as yet been decided: 

"Technical Limitations and Possible 
Application of 16-Mm Film in 
Broadcasting and Television," by 
J. A. Maurer, J. A. Maurer, Inc. 

"16-Mm Motion Pictures for Tele- 
vision," by Jerry Fairbanks, Jerry 
Fairbanks, Inc. 

"Some Photographic Contrast Con- 
siderations for Television," by Fred 
Albin, Radio Corporation of 

"Stereophonic Magnetic Recording," 
by M. Camras Armour Research 

"Magnetic Sound for 8-Mm Motion 
Pictures," by H. A. Leedy, Armour 
Research Foundation 

"Variable- Area Sound Track on 16-Mm 
Kodachrome," by R. V. McKie, 
Radio Corporation of America, and 
R. G. Hufford and N. L. Simmons, 
Eastman Kodak Company 

"A Silent Playback and Public-Address 
System," by Bruce Denney and 
Robert J. Carr, Paramount Pictures 

"Synchronized Sound and 8-Mm Pic- 
tures," by Phil Goldstone, Phono- 
vision Corporation 

"Developer Analysis for Laboratory 
Control Procedures," by Ansco 

"Ansco Motion Picture Film Labora- 

tory," by Ansco 

"New Motion Picture Processing Ma- 
chines," by William Prager, Arto- 
chrome Motion Picture Laboratories 

"Report of Committee on High-Speed 
Photography," by A. P. Neyhart, 
Douglas Aircraft Company 

"Report of Standards Committee," by 
F. T. Bowditch, National Carbon 

"Animation," by Karel Dodal, Irena 
Film Studios 

"An Improved Camera Crane," by 
Research Council Staff Member 

"The Motion Picture Research Coun- 
cil Its Functions and Activities," by 
W. F Kelley, Motion Picture Re- 
search Council 

"Restoration of Early Motion Picture 
Films," by Howard Walls, Academy 
of Motion Picture Arts and Sciences 

"Visual Education," by Donald Doane, 
University of Southern California 

"Some Technical Problems Associated 
with the Foreign Release of Ameri- 
can Motion Picture Films," by Ran- 
dal Terraneau, Humphries Labora- 
tories, England 

"The Use of Photography in the Naval 
Antarctic Expedition," by Naval 
Photographic Center 



Hotel Reservations 

Because out-of-town members and guests will attend the 63rd Semiannual 
Convention at the Santa Monica Ambassador Hotel and the Del Mar Beach Club, 
which is directly across the street from the Ambassador, the Pacific Coast Sec- 
tion officers have appointed a local housing committee under the chairmanship 
of Mr. Watson Jo.nes, Radio Corporation of America, 1016 North Sycamore Street, 
Hollywood 38, California. There will'be no room-reservation cards mailed to the 
membership, so all requests for room accommodations should be mailed or wired 
direct to Watson Jones. He will book, assign, and confirm all reservations sent to 
his attention. 

Send your room reservations requests to Mr. Jones as early as possible. They 
are subject to date change, or cancellation, not later than May 10, 1948. 

Room Rates 

The following European Plan rates are extended SMPE members and guests 
attending the 63rd Semiannual Convention: 

Single rooms with bath, $5.00-16.00 

Double rooms, with twin beds and bath, $7.00-$8.00-$9.00 
There are a few parlor suites at the Santa Monica Ambassador Hotel at 
$17.50 per day. 

NOTE: The housing committee will have available additional rooms or bunga- 
lows at the Hotel Miramar in Santa Monica, which is about five blocks from con- 
vention headquarters. 

When booking your room reservation with Watson Jones, be sure to specify the 
type of accommodations desired, day rate, a-nd date of your arrival at Santa 
Monica, California. Please co-operate to insure your hotel reservations. 

NOTE: Transportation, Los Angeles to Santa Monica: Out-of-town members 
and guests arriving in Los Angeles by train can take a taxi at the Los Angeles 
Union Station and go to Fifth and Hill Streets in Los Angeles, board a Los Angeles 
Railway Santa Monica Express motor coach which travels out Wilshire Boule- 
vard direct to Santa Monica, and debark at the station within one block of the 
hotel. The distance from Los Angeles to Santa Monica is about 20 miles. If 
taxi transportation is used the fare will be about $5.00. 

Rail, Pullman, and Plane Travel 

Travel is still heavy and your Convention Committee suggests that you consult 
your local travel agent for rail, pullman, or plane accommodations to the West 
Coast and return, at least 30 days prior to your departure for Santa Monica. 

Convention Registration and Papers Program 

The Convention Papers Committee can only function successfully in the early 
assembly and scheduling of the Convention Papers Program by receiving the title 
of papers to be presented, name of the author, and a complete manuscript mailed 


to N. L. Simmons, 6706 Santa Monica Blvd., Hollywood 38, California, not later 
than May 1, 1948. 

The Convention business and technical sessions will be held in the Magnolia 
Room on the sixth floor of the Santa Monica Ambassador. Registration head- 
quarters will be set up at the entrance of the Magnolia Room. 

Members and guests attending the Convention are expected to register and 
receive their Convention badges and identification cards. Registration fees are 
used to defray the Convention expenses. 

Convention Get-Together Luncheon 

- The Convention Get-Together Luncheon will be held in the Ocean Room of the 
Del Mar Beach Club, at 12:30 P.M. on May 17. Eminent speakers and enter- 
tainment are assured by the Luncheon Committee. 

The luncheon fee will be $2.50 per person, State Tax and gratuity included. 
The ladies attending the Convention are invited to attend this luncheon. Lunch- 
eon tickets should be procured in advance of the date of this function, either 
through the Pacific Coast Section Secretary, or W. C. Kunzmann, Convention 
Vice-Preside nt, during the week of May 9, at the Santa Monica Ambassador Hotel 
or at the registration headquarters prior to 11 : 00 A.M. on May 17 so that seating 
accommodations can be provided. There will be no seating guaranteed for 
holders of tickets purchased after 11 :00 A.M. on May 17. 

Cocktail Hour 

Holders of banquet tickets will be entertained at a social get-together 
"Cocktail Hour" in the Rouge Room on the fourth floor of the Santa Monica 
Ambassador Hotel, on May 19, between 7:15 P.M. and 8:15 P.M. 


The Convention informal banquet (dress optional) will be held in the 
Magnolia Room on the sixth floor of the Santa Monica Ambassador Hotel on 
May 19, promptly at 8:30 P.M. This is your night for social get-together. En- 
tertainment and dancing until 12 : 30 A.M. 

The fee per person for Banquet tickets will be $10.00, Federal Amusement 
and State Tax included, also the gratuity. Tickets for this function must be 
procured prior to noon on May 19, so that seating can be provided. Book table 
reservations at the Convention registration headquarters. 

Ladies' Program 

The Ladies' Committee will have open house, and register the ladies attending 
the Convention in the Recreation Room of the Santa Monica Ambassador Hotel 
during the Convention dates. 

Mrs. S. P. Solow, the Convention Hostess, and members of her committee assure 
the ladies attending the Convention an attractive and interesting entertainment 
program, which will be announced by the Ladies' Committee at a later date. 

Motion Pictures 

The Convention identification card issued to registered members and guests is 
your means of identification at all scheduled sessions held at, and away from, the 


hotel. This card will also -be honored at the following de luxe motion picture 
theaters in Hollywood and Santa Monica during the Convention. 

In Hollywood, the Convention identification card will be honored at the 
Pantages, Paramount, and Warner Brothers theaters located on Hollywood 
Boulevard. The Fox West Coast Theaters Corporation will issue special passes 
which will be honored at the Grauman's Chinese and Egyptian theaters in Holly- 
wood and at the Criterion and Dome Ocean Park theaters in Santa Monica during 
the Convention. 


A variety 9f recreational benefits and privileges can be enjoyed by those who 
register at Santa Monica hotels. These include roof solarium at the Santa 
Monica Ambassador Hotel, ocean-front walk, ocean sport fishing, bathing, golf, 
tennis, and horseback riding. 

There are auto parking facilities at the Santa Monica Ambassador Hotel. 
Excellent transportation is available to all points of interest in the greater Los 
Angeles area. Consult the Convention registration headquarters for information 
pertaining to recreation and transportation to points in the immediate vicinity of 
Santa Monica. 


Atlantic Coast 
Chairman Secretary-Treasurer 

William H. Rivers Edward Schmidt 

Eastman Kodak Co. E. I. du Pont de Nemours & Co 

342 Madison Ave. 350 Fifth Ave. 

New York 17, N. Y. New York 1, N. Y. 


Chairman Secretary-Treasurer 

R. T. Van Niman George W. Colburn 

Motiograph George W. Colburn Laboratory 

4431 W. Lake St. 164 N. Wacker Dr. 

Chicago 24, 111. Chicago 6, 111. 

Pacific Coast 

Chairman Secretary-Treasurer 

S. P. Solow G. R. Crane 

Consolidated Film Industries 212 24 St. 

959 Seward Santa Monica, Calif. 

Hollywood, Calif. 

Student Chapter 
University of Southern Calfornia 
Chairman Secretary-Treasurer 

Thomas Gavey John Barn well 

1046 N. Ridgewood PI. University of Southern 

Hollywood 38, Calif. California 

Los Angeles, Calif. 

1948 Nominations 

The 1948 Nominating Committee, as appointed by the President of the Society, 
was confirmed by the Board of Governors at its January meeting. 

40 Charles Street 
Binghamton, New York 

18 Cameron PI. 
New Rochelle, N. Y. 

Warner Bros. Pictures 
Sound Department 
Bur bank, California 


Eastman Kodak Company 
6706 Santa Monica Blvd. 
Hollywood, California 

Los Alamos Laboratory 
University of California 
Albuquerque, New Mexico 


2237 Mandeville Canyon Road 

Los Angeles 24, California 


RCA Victor Division 

Radio Corporation of America 

Engineering Products Department 10-4 

Camden, New Jersey 


Electrical Research Products Division 
6601 Romaine 
Los Angeles, Calif. 


7100 McCormick Road 
Chicago 45, Illinois 

All voting members of the Society who wish to submit recommendations for 
candidates to be considered by the Committee as possible nominees, are re- 
quested to correspond directly with the Chairman or any of the members of the 
Nominating Committee. Active, Fellow, or Honorary Members are authorized 
to make these suggestions which must be in the hands of the Committee prior to 
May 1, 1948. 

There will be ten vacancies on the Board of Governors as of January 1, 1949, 
which must be filled. Those members of the Board whose terms of office expire are : 

Governor JOHN W. BOYLE 


Governor. . . . CHARLES R. DAILY 

President LOREN L. RYDER 

Executive Vice- 

Editorial Vice- 
President. . . . .CLYDE R. KEITH 

Convention Vice- 



The recommendations of the Nominating Committee will be submitted to the 
Board of Governors for approval at the July meeting. The ballots will then be 
prepared and mailed to the voting members of the Society forty days prior to the 
Annual Meeting of the Society which is always the opening business session of the 
Fall Convention. This year it falls on Monday, October 25, and the Convention 
will be held at the Statler Hotel in Washington, D. C. 

E. ALLAN WILLIFORD, Chairman, Nominating Committee 


Section Meetings 


Mr. Frank E. Carlson, Illuminating Engineer in the Lamp Department of the 
General Electric Company, at Nela Park, spoke on "New Developments in Mer- 
cury Lamps for Motion Picture and Television Studio Lighting"* at the January 
8, 1948, meeting of the Midwest Section. The paper described a cadmium-mer- 
cury source developed in England and showed its adaptation to standard lighting 
equipment units. Technicolor motion pictures and slides demonstrated its 
qualities with direct comparisons of material photographed with carbon-arc 
sources and the mercury source. Discussion brought out the fact that although 
many types of this light source are being developed in the United States, it will be 
some time before they will be available commercially. 

Appreciation was expressed to the Eastman Kodak Stores for the use of two 
1000- watt Master Kodaslide projectors and to the DeVry Corporation for a 35- 
mm projector. 

There was a short business section at which was read the report of the last meet- 
ing and the financial report for the year ending December 31, 1947. 

* Presented September 30, 1947, before the Pacific Coast Section; published, 
JOURNAL OF THE SMPE, February, 1948, pp. 122-139. 

Atlantic Coast 

At the February 18, 1948, meeting of the Atlantic Coast Section, L. A. Mea- 
cham, Research Engineer for the Bell Telephone Laboratories, presented a paper 
on "An Experimental Multichannel Telephone Transmission System Employing 
Pulse-Code Modulation". Mr. Meacham pointed out that speech or music 
translated into patterns of standardized on-off pulses may be transmitted by 
radio relay over any distance without accumulating noise or distortion. The 
problems involved in applying this technique (pulse-code modulation) to multi- 
plex telephony have been explored in terms of a 96-channel system designed to 
transmit speech with commercial toll quality. Novel components of the system 
were described, including an electron-beam coding tube, the "Shannon-Rack 
decoder", pulse slicers, sampling circuits, and an instantaneous amplitude com- 

The demonstration allowed the audience to judge the quality of transmission of 
speech and music obtained with different numbers of characters in the pulse code. 


On page 86 of the January, 1948, issue of the JOURNAL, the business affiliation 
of Mr. C. C. Dash, president of the Hertner Electric Company, was given in- 
correctly. The Fellow 'Award citation should read as follows: 

C. C. DASH, Hertner Electric Company, 

"for the design and manufacture of motor-generator sets used extensively in 

the motion picture industry." 

Book Reviews 

The Architects Manual of Engineered Sound Systems 

Published ^1947) by the Radio Corporation of America, Camden, N. J. 284 
pages plus 4-page index. Profusely illustrated. 9 x /2 X 11 inches. Price, $5.00. 

Intended for the use of architects and others interested in the design of sound- 
distribution systems, the Manual is divided into two principal parts. The first 
section deals with Definitions, Graphical Symbols, The Microphone, The Ampli- 
fier, The Loudspeaker, Controls, Studios and Control Rooms, Acoustics, The 
Sound Film Projector (16-mm and 35-mm), and Antenna Systems. This section 
is not intended as an engineering text and the subject matter consequently is 
treated in an elementary fashion. It is obvious that the viewpoint of the architect 
and the layout designer is kept in mind. Architectural and engineering specifica- 
tions for each equipment subject are included. The treatment is, generally, ex- 
cellent though essentially nontechnical. A possible oversight, perhaps intentional, 
is noted in the failure to include definite recommendations for available amplifier 
power requirements in enclosures. 

The second section covers Typical Layouts and Specifications. Suggested lay- 
outs are included for one or more of the following: Schools, Hospitals, Churches, 
Auditoriums, Stores, Industrials, and Hotels. Some treatments are very de- 
tailed in breakdown of departments. Specifications are set up around RCA 

The Manual does not give the architect every element of information that 
might be required such as, for example, the correction of acoustic difficulties, 
although the treatment of the subject conforms to the more-or-less standard 
method of the elementary text. Neither the acoustic engineer nor the communi- 
cations engineer is completely by-passed even assuming the architect to be letter- 
perfect in his acquaintance with the Manual's contents. C. S. PERKINS 

Altec Service Corporation 
New York 19, N. Y 

Television Volume III (1938-1941) 
Television Volume IV (1942-1946) 

Edited by Alfred N. Goldsmith, Arthur F. Van Dyck, Robert S. Burnap, Ed- 
ward T. Dickey, and George M. K. Baker. Published by RCA Review, RCA 
Laboratories, Princeton, N. J. Volume III (1938-1941). 486 pages + xii 
pages. 288 figures. 6X9 inches. Price, $2.50. Volume IV (1942-1946) 
498 pages + 12-page Appendix + xiv pages. 301 figures. 6X9 inches. Price, 

These two books continue the series established in 1936, which reprint the most 
significant papers published in the field of television by the RCA organization, 
with the addition of a few original articles. 

Perusal of these volumes brings out .strikingly the breadth of the field which 
must be explored and developed to build up the art of television, and the variety 
of effort expended upon it by one organization. It is handy to have this diversity 
of material brought together compactly in such a manner. This is especially 



true for the motion picture engineer, to whom the changes in his art that may be 
brought about by the arrival of television constitute a provocative challenge. 

The range of material presented has been classified as follows: 

Pickup, in which the new development of the image orthicon is described, and 
the problems of studio and field television are treated. 

Transmission, which covers, on the one hand, video signals and their propaga- 
tion around the building, and, on the other hand, radio in its many aspects over 
the wide ranges of frequency used for the various purposes in the art. 

Reception, comprising discussions on images produced by cathode rays and the 
methods of their projection, and covering the problems of receiving sets sold to the 
general public. 

Color Television, summarizing work done by the RCA organization in this field. 

Military Television, where are assembled the results of RCA television contribu- 
tions to the war effort. 

General, which is an assay of what the impact of this new art of television may 
be on our daily life in the coming years. PIERRE MERTZ 

Bell Telephone Laboratories 
New York 14. N. Y. 


It is highly desirable that members avail themselves of the opportunity 
to express their opinions in the form of Letters to the Editor. When of 
general interest, these will be published in the JOURNAL of the Society of 
Motion Picture Engineers. These letters may be on technical or non- 
technical subjects, and are understood to be the opinions of the writers and 
do not necessarily reflect the point of view of the Society. Such letters 
should be typewritten, double-spaced. If illustrations accompany these 
contributions, they should be drawings on white paper or blue linen and 
the lettering neatly done in black ink. Photographs should be sharp 
and clear glossy prints. 

Please address your communications to 

Miss HELEN M. STOTE, Editor 

Society of Motion Picture Engineers 

Suite 912 

342 Madison Avenue 

New York 17, N. Y. 


rriHE EDITORS present for convenient reference a list of articles dealing with 
JL subjects cognate to motion picture engineering published in a number of 
selected journals. Photostatic or microfilm copies of articles in magazines that 
are available may be obtained from The Library of Congress, Washington, D. C., 
or from the NewTork Public Library, New York, N. Y., at prevailing rates. 

American Cinematographer 

28, 12 (Dec., 1947) 
Special Photographic Effects Magic 

(p. 431) G. JOHNSON 
40 Years for Bell and Howell (p. 434) 
Television Recording Camera De- 
veloped by Eastman Kodak 
(p. 436) 

British Kinematography 

11, 5 (Nov., 1947) 
The Ansco Color Process (p. 142) 


Fluorescent Lighting (p. 155) 


11, 6 (Dec., 1947) 
The Film in Relation to Television 

(p. 177) M. COOPER 
Recent Developments in Carbon 

Arc Lamps (p. 188), C. G. HEYS- 

Problems of 16 mm Production 

(p. 198) J. P. CHAPMAN, S. SCHO- 


Ideal Kinema 

13, 149 (Dec. 4, 1947) 
Television Pictures from Kinemato- 
graph Film (p. 19) A. BUCKLEY 

International Photographer 

19, 12 (Dec., 1947) 

20 Years of Starlighting (p. 5) 

"False Color" Film for (Aerial Pho- 
tography (p. 18) 

20, 1 (Jan.,. 1948) 

Lighting for Technicolor as Com- 
pared with Black and White 
Photography (p. 7) J. VALENTINE 

The New Maurer 16 mm Camera 
(p. 12) F. GATELY 

International Projectionist 

22, 12 (Dec., 1947) 

The Peerless Hy-Candescent Arc 
Lamp (p. 5) H. B. SELLWOOD 

Startling Soviet Stereo Films (p. 17) 

Historical Development of Sound 
Film. Pt. 6 (p. 19) E. SPONABLE 

Met to Film Operas in Color (p. 27) 
23, 1 (Jan., 1948) 

Factors Affecting Image Steadiness 
(p. 5) R. A. MITCHELL 

Lead-Sulfide Photo conductive Cells 
(p. 8) R. J. CASHMAN 

Projection Equipment, Technique in 
'47 (p. 12) H. B. SELLWOOD 

The Vitascope Dual-Purpose Pro- 
jector (p. 17) L. CHADBOURNE 

Radio News 

39, 2 (Feb., 1948) 

Build Your Own Magnetic Tape Re- 
corder (p. 39) L. B. HUST 
Magnetic Tape Systems (p. 46) 


The Recording and Reproduction of 
Sound. Pt. 12 (p. 56) O. READ 

Radio News (Radio-Electronic 

39, 2 (Feb., 1948) 
Sound on Tape (p. 3) J. D. GOODELL 


Journal Exchange 

Mr. O. C. Johnson would like to buy 
a copy of the January, 1946, issue of 
the JOURNAL of the SMPE. Since 
these copies are no longer available 
from the Society, it would be appre- 
ciated if anyone having an extra copy 
or one for sale would communicate 
with MR. O. C. JOHNSON, Westrex 
Corporation, 111 Eighth Avenue, New 
York City. 

Mr. Jack K. Leatherman, 2138 
Thacker Avenue, Jacksonville, Fla., 
has twenty-four copies of the JOURNAL 
which he wishes to sell. These are in 
good condition, and are from July, 
1945, through June, 1947. Anyone 
wishing to purchase them should write 
to Mr. Leatherman at the address 
given above. 

Mr. David M. Baltimore has the 1 
following eighteen issues of the JOUR- 
NAL which he would like to trade for 
certain others that are missing from 
his library: 1930, April; 1931, Febru- 
ary; 1932, April, June, July, August, 
November, and December; 1933, 
all except June, July. 3 Indexes 
July, 1916, to June, 1930. 

Any members who have JOURNALS in 

the following list which they would like 
to trade for those listed in the opposite 
column should correspond directly with 
ington Street, Elmira, New York: 
1940, October; 1941, March, June, 
August, November, December; 1943, 
April to December, inclusive; 1944, 
entire year; and 1945, January to 
June, inclusive. 

The Society of Motion Picture Engi- 
neers has for sale certain back copies of 
as listed below. 


Numbers 3, 4, 10, 11, 12, 13, 14, 15, 17, 
19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 
and 32 at $1.25 each; 33, 34, 35, and 
36 at $2.50 each; and 37, and 38 at 
$3.00 each. 

JOURNALS $1.25 each 

Entire Year: 1930, 1931, 1935, 1937, 
1942, 1943, and 1947. 
1932 no May 

1933 no May, June, October 

1934 no January, February, March, 


1936 no April, May 
1937 no April, May 
1938 no January, March, May 
1939 no April 
1940 no June 
1941 no March and July 
1944 no. February, March, May, July 
1945 no August 
1946 no January, February, March 

Send your order with remittance to 
the Society of Motion Picture Engi- 
neers, 342 Madison Avenue, New 
York 17, N. Y. 

Journal of the 

Society of Motion Picture Engineers 



Advancement of Motion Picture Theater Design 


The Psychology of the Theater WALTER A. CUTTER 314 

General Theater Construction JOHN J. McNAMARA 322 

Influence of West Coast Designers on the Modern Theater 


The Drive-In Theater S. HERBERT TAYLOR 337 

Foreign Theater Operation CLEMENT CRYSTAL 344 

Seating Arrangements, Sight Lines, and Seating Design 

Increasing the Effectiveness of Motion Picture Presentation . . . 


Dynamic Luminous Color for Film Presentation 


The New Slide-Back Chair W. A. GEDRIS 389 

Officers of the Society 393 

Governors of the Society 395 

Constitution and Bylaws 397 

Awards '. 408 

Membership and Subscription Report 412 

Report of the Treasurer .' 

Society Announcements 414 

Current Literature 415 

63rd Semiannual Convention Tentative Program 416 


Chairman Editor Chairman 

Board of Editors Papers Committee 

Subscription to nonmembers, $10.00 per annum; to members, $6.25 per annum, included in 
their annual membership dues; single copies, $1.25. Order from the Society's general office. 
A discount of ten per cent is allowed to accredited agencies on orders for subscriptions and 
single copies. Published monthly at Easton, Pa., by the Society of Motion Picture Engineers, 
Inc. Publipation Office, 20th & Northampton Sts., Easton, Pa. General and Editerial Office, 
342 Madison Ave., New York 17, N. Y. Entered as second-class matter January 15, 1930, 
at the Post Office at Easton, Pe. under the Act of March 3, 1879. 

Copyright, 1948, by the Society of Motion Picture Engineers, Inc. Permission to republish 
material from the JOURNAL must be obtained in writing from the General Office of the Society. 
Copyright under International Copyright Convention and Pan-American Convention. The 
Society is not responsible for statements of authors or contributors. 

Society of 

Motion Picture Engineers 

342 MADISON AVENUENEW YORK 17, N. Y. TEL. Mu 2-2185 




Loren L. Ryder 

5451 Marathon St. 

Hollywood 38, Calif. 

Donald E. Hyndman 

342 Madison Ave. 

New York 17, N. Y. 

Earl I. Sponable 

460 West 54 St. 

New York 19, N. Y. 


Clyde R. Keith 

233 Broadway 

New York 7, N. Y. 

William C. Kunzmann 

Box 6087 

Cleveland, Ohio 

G. T. Lorance 

63 Bedford Rd. 

Pleasantville, N. Y. 



John A. Maurer James Frank, Jr. 

37-0131 St. 18 Cameron PI. 

Long Island City 1, N. Y. New Rochelle,' N. Y. 


Ralph B. Austrian 
247 Park Ave. 
New York 17, N. Y. 

John W. Boyle 

1207 N. Mansfield Ave. 
Hollywood 38, Calif. 
David B. Joy 
30 E. 42 St. 
New York 17, N. Y. 



Robert M. Corbin Charles R. Daily ' 

343 State St. 5451 Marathon St. 

Rochester 4, N. Y. - HoUywood 38, Calif. 
Hollis W. Moyse 

6656 Santa Monica Blvd. 
Hollywood, Calif. 

William- H. Rivers 
342 Madison Ave. 
New York 17, N. Y. 

Alan W. Cook 
4 Druid PI. 
Binghampton, N. Y. 


S. P. Solow 
959 Seward 
Hollywood, Calif. 


Lloyd T. Goldsmith 

Burbank, Calif. 
Paul J. Larsen 

Los Alamos Laboratory 
University of California 
Albuquerque, N. M. 

R. T. Van Niman 
4431 W. Lake St. 
Chicago, 111. 

Gordon E. Sawyer 
857 N. Martel 
Hollywood, Calif. 

Theater Engineering Conference 

Introductory Session . 

Advancement of Motion Picture 
Theater Design* 



Summary During the past twenty years, great advances have been made 
in motion picture theater design and in theater engineering. The builder, 
architect, and equipment manufacturers have come to recognize the value of 
co-ordinating their work in order that an attractive, comfortable, well- 
equipped theater might result. There are outlined here some of these ad- 
vances and some of the problems which have been studied in this connection. 

WITH THE ADVENT of this convention the science and art of motion 
picture 'theater design becomes a recognized and worth-while 
endeavor. This is attested to by the fact that a large part of this 
convention is being devoted to a Theater Engineering Conference. 
At the 1931 Spring Convention of this Society in Hollywood, Mr. 
Crabtree saw the need for much improvement in motion picture 
theater design and he has been a consistent advocate of allowing the- 
ater engineering an important place in the scope of 'the work of the 
Society of Motion Picture Engineers. I proposed at that Convention 
sixteen years ago, that the motion picture theater had not yet de- 
veloped a form that was necessary for the proper functioning of the art. 
Until the period following that Hollywood Convention/ there really 
was no theater that properly could be called a motion picture theater. 
The motion picture itself developed so fast that it had to be housed in 
buildings originally intended for stage presentations or in buildings 
which were intended for motion picture use but necessarily had to 
mimic the stage theater because the art and science of motion picture- 
theater design could not conceivably have. advanced rapidly enough 
to keep up with the great strides made in the film industry. Theater 

* Presented October 20, 1947, at the SMPE Convention in New York. 


304 SCHLANGER April 

buildings are not built on a production-line basis. They are built 
scarcely more than one at a time by any one interest and, therefore, 
there could not be much individual initiative for the research that was 
necessary to advance theater design. This fact makes it necessary 
for organizations of the motion picture world to take the initiative in 
sponsoring research and standardization. This Society seems to have 
recognized this point increasingly as its past and present activities 
show. That it has called this Convention and arranged this program 
indicates that it will be of important service in making possible 
theater engineering design which will keep pace with the advance- 
ments made in motion picture art. 

At this point it would be interesting to note how a motion picture 
theater was built approximately twenty years ago, today, and how it 
should be built under more favorable conditions. More recently the 
benefits of an architect's services have been increasingly recognized 
and there are less and less instances of -theater structures being con- 
structed without professional guidance. The architects have been 
capable of designing structures which keep the elements out and even 
prove attractive but they have not until recently realized the im- 
portance of theater engineering. Their designs and even their 
structures would be well advanced when scattered information from 
equipment manufacturers would be referred to. Sometimes the 
equipment manufacturer would be called in when it proved too costly 
to make changes to conform with engineering requirements. The 
contemporary theater architect must have an up-to-date knowledge 
of theater engineering, and depend on information from equipment 
manufacturers only to supplement his basic theater engineering 
knowledge. We are entering a period when the motion picture 
theater structure will be completely conceived on paper for ever}^ 
engineering function as well as the architectural considerations, 
thereby eliminating the trial-and-error methods in the construction 
phase of the work. 

Just to show how much progress we are making, I am no longer the 
lone theater architect at these Conventions. You are going to hfcar 
from other architects and this is certainly a sign of progress because 
these architects in coming here surely must now be aware of the im- 
portance of the engineering functional aspects of theater design. We 
are certainly now past the period in which the motion picture theater 
auditorium design was thought of too much as a surface decorative, 
and not enough as a functional engineering problem. 


There was a time in the history of this Society and motion picture 
design when it was difficult to be convincing enough as to the im- 
portance of theater engineering. That was when I had to be a mem- 
ber of the Projection Practice Committee of the Society of Motion 
Picture Engineers in order to promote engineering study for the en- 
tire theater structure. Yes, I worked for the rest of the theater from 
up there in that projection room until we* found ourselves with a 
Theater Engineering Committee, and today we begin this important 
Theater Engineering Conference. I earned my seat in the Projection 
Practice Committee because I advocated theater design principles 
that led to the reduction of projection angles. They always re- 
minded me of the architect who forgot to include a projection room in 
his design. The work done in this committee was really the begin- 
ning of theater engineering and can be considered a notable contri- 
bution in this field. 

A theater survey study, a subcommittee activity of the Projection 
Practice Committee of this Society, can be considered one of the most 
important early developments in theater engineering research. A 
great many of the theaters that were checked in this survey were built 
originally for stage performances or for a combination of stage and 
film presentations. A similar survey made at this time may prove 
exceedingly valuable since the original survey was made in 1938. 
The observations noted in the analysis of this early survey have 
proved most valuable in theater engineering study, and it is still the 
basis for further work being done. A brief review of this early survey 
is now pertinent and here are some of the high lights. 

1. ^Projection, screen, and viewing conditions varied over an ex- 
tent of at least three times what might be considered tolerable. 

2. For theaters built between 1930 and 1938 only 27 per cent had 
satisfactory conditions for motion picture presentation. The lack of 
published standard requirements was evident. Fulfillment of satis- 
factory viewing conditions was a matter of chance and not of inten- 

3. Indications were that practical limitations were not the only 
causes of undesirable conditions. 

4. Seating capacities became steadily smaller; 26 per cent of the 
theaters erected before 1930 had capacities of over 1500 with only 10 
per cent of the theaters erected after 1930 with such capacity. 

5. The theaters having over 2000 capacity showed a greater num- 
ber of seats subject to undesirable viewing conditions. 

306 SCHLANGER April 

6. The following principles determining the ideal motion picture 
theater form, considered from a purely technical standpoint, may 
develop into a form that may not in some instances fulfill all the rigid 
requirements set forth for the commercial motion picture theater : yet 
it is the obligation of the Society to indicate what would be the most 
desirable form of theater, and all those who are concerned with the 
design of theaters may adhere as closely to recommendations as may 
be 'practically possible. 

The basic design of the motion picture theater depends more than 
anything else upon the ability to view satisfactorily the picture. The 
factors involved are: 

A. Picture Detail (visual acuity) 

(1) Screen size in relation to viewing distance 

(2) Screen brightness 

(3) Contrast 

B. Obstruction of View 

(1) By other spectators 

(2) By fixed parts of the structure 

C. Distortion of Picture 

(1) In projection 

(2) In viewing 

D. Angle of View (affecting posture and bodily comfort) 

(1) Horizontal 

(2) VerticaL 

E. Psychological 

While this Conference is certain to prove valuable in exposing im- 
portant technical data, it may well be remembered more as the turn- 
ing point at which the motion picture has reached an important 
enough stage to justify buildings carefully and specifically designed 
for its use. The timing of this Convention seems to be quite logical. 
Perhaps it was necessary to take these past years since the advent of 
sound to convince the investor that theaters can be constructed for the 
motion picture art alone and prove a good risk. However with ear- 
lier recognition of the soundness of this risk, there would now be a far 
smaller number of substandard theaters. 

It is hoped that at this time we can take the definite stand that no 
compromise need be made so that a theater building would have to 
house the stage performance as well as film exhibition. Any compro- 
mise in theater design in this respect will produce a theater which is 
not good enough for either of the arts, visually, acoustically, or 




psychologically. The Theater Engineering Committee made further 
investigations as to viewing positions and picture size and also made a 
contribution toward creating a nomenclature of theater engineering. 

Refering to the basic factors A, B, C, D, and E which determine the 
form of the motion picture theater, there are now considerable data 
available for solving the problems of factors B and C. However fac- 
tors A, D, and E require a good deal of research. The determination 
of the advisable maximum viewing distance to the screen as fixed by 
past practice is subject to revision because a study has to be made of 
cinematographic practice in relation to this problem. Also it may 
very well be possible .to have seating positions farther away from the 
screen than six times the picture 
width if the auditorium surfaces 
were so treated as to not let the 
spectator feel the distance from 
the picture to his seat. Most 
architectural treatments in exist- 
ing motion picture theaters tend 
to emphasize rather than dimin- 
ish the space between the pic- 
ture and the viewer. 

There are now sufficient data 
on hand to enable us to stand- 
ardize on methods of determining 
sight-line clearances. A seem- 
ingly unimportant dimension 
such as. measuring from a per- 
son's eye to the top of the head, 

becomes a key dimension for calculating sight-line clearances. We 
shall have to establish this measurement. We now appreciate 
that the angle subtended to an average image on the motion 
picture screen can be approximately five times as great as the 
angle subtended to a group of two or three human figures on a stage in 
a fle*sh performance. (See Fig. 1.) This fact makes it necessary to 
so locate each theater chair so as to enable the viewer a wider clear 
view of the screen image in looking between the heads of the preceding 
spectators. Fig. 1 shows one of the important differences between 
stage and cinema theater design. On the top sketch you see the 
spectator and the angle subtended to what might be considered the 
amount of horizontal screen dimension that may have to be seen quite 

Fig. 1 

308 SCHLANGER April 

frequently throughout a film presentation. On the bottom sketch 
you see the angle subtended from the spectator to some characters and 
a prop on a stage set. I often wondered why there were not more 
complaints about sight-line clearances in stage theaters since the head 
in front of the spectator was always an obstruction. This diagram 
should prove as enlightening to you as it has to me on this subject. 
The spectator would find it annoying to move his head to one side or 
the other to see around the head in front, but the amount of move- 
ment necessary to see the small subtended angle in the case of the 
stage theater is small enough to make the spectator head moving 
tolerable. This is especially so with the stage performance because 
the characters ordinarily do not shift often enough or to a great 
enough extent to cause the spectator annoying enough shifting of the 
head. Now we had inherited the theater form of the stage for motion 
picture presentation and the annoyance of head shifting bec*ame intol- 
erable because, as the diagram shows, the larger image width and the 
ability for even a smaller image on the screen to flit about swiftly in- 
troduced new considerations. 

Effective methods have been developed and successfully employed 
for staggering the seating to achieve the necessary amount of clear- 
ance of view between the heads of the preceding spectators. This is 
a notable development, especially since it can be used also in improv- 
ing sight lines by reseating existing theaters. Floor slopes for motion 
picture theaters would have become intolerably excessive if any at- 
tempt were to be made to gain vision over the heads of preceding spec- 
tators. The progress made, in staggered-seating design in conj unction 
with the successful development of what was originally called the 
"reverse floor slope" and is now being recognized as a "dual incline 
floor," has developed a theater form which is purely inspired by the 
functions of viewing a motion picture. This new theater form was 
made possible because sight lines onto a motion picture screen (a ver- 
tical plane which is not necessarily fixed in position) presented a 
flexibility in design which was not possible for the stage theater be- 
cause the stage (a horizontal plane) is necessarily fixed in position, a*nd 
therefore limited the number of solutions to the floor-slope problem. 

We have yet to determine by scientific testing, the tolerable and 
desirable angles of view upward and downward to the picture. The 
quality of a theater design from a patron-comfort standpoint is very 
much affected by this yardstick. Spectators in upper-level seating 
should not experience excessive downward viewing and those seated 






310 SCHLANGER April 

on the main floor should not experience .excessive upward viewing. 
The ideal design would present the largest precentage of seating po- 
sitions for the entire theater affording desirable vertical angles of view. 
Excessive floor slopes pitching downward only have in the past af- 
forded better than necessary vertical viewing angles for the main 
floor seating while such slopes created upper-level seating from which 
the downward viewing angles proved much too excessive. Fig. 2 
shows two contemporary examples of theaters now being completed 
incorporating these latest principles of design. There are now 
theaters all over the world constructed in this manner. (See Bib- 
liography for examples.) There are also several hundred theaters 
built incorporating these ideas in whole or in part hi which instances I 
have not participated in their design. In these theaters constructed 
by persons not fully versed in the medium, the quality in some 
instances may have suffered. 

The earliest examples in which the reverse floor slope was used with 
a screen position that was somewhat too high were greatly improved 
upon when experience in what would be considered desirable upward 
viewing was better established. 

Upper level seating has become very desirable because viewing 
distances and screen image sizes are decreased thereby. Or if a 
relatively larger screen image is desirable the shorter viewing dis- 
tance will always make this possible. Upper-level seating also makes 
it possible to place more desirable viewing positions on a given area 
of ground space. With contemporary design methods such as illus- 
trated in Fig. 2, upper-level seating can be at a comfortable level with 
relation to the picture level, and projection angles can be kept well 
within recommended limits. A maximum of 12 degrees has been es- 
tablished by the American Standards Association. In Fig. 2B, where 
two upper levels are shown in the Tacna Theatpr, it was possible to 
adhere to this limitation. This is the first example of a workable 
motion picture theater with two upper levels of seating where this 
was made possible. 

In Fig. 2A, the theater with the single upper level of seating is out- 
lined in solid and dotted lines, the solid lines being the advanced type 
of design and the dotted line being the type of theater influenced by 
the stage performance. This comparative study shows the unproved 
downward viewing angles for the balcony viewing positions and the 
negligible increase in the upward viewing angle for the orchestra seat- 
ing positions. Note that the new orchestra floor is lower in relation 


to the level of the screen to any appreciable amount, only for the por- 
tion farthest from the screen. This lowering of the floor does not 
create any annoying upward viewing because the distance from the 
screen places the screen well within the normal range of vision. So 
that at no sacrifice in the quality of the orchestra seating, the bal- 
cony seating positions are improved considerably. The relative flat- 
ness of the orchestra floor slope is also a distinct improvement over 
the steep pitches formerly used. Another distinct improvement in 
these new forms is the elimination of the requirement for the familiar 
intermediate step in the balcony aisles, the extra step which had to be 
used to get from the level of one seating platform to the next. Since 
this step had to be shorter than the rest of the platform, it has always 
caused a hazard and most of the accidents in theater aisles have been 
due to this fault. Because the pitches of the balconies in the new thea- 
ter form can be much less severe, there is no need for the extra short step 
between seating platforms. This is so even in the scheme with the 
two upper levels, which is the Tacna Theater in Lima, Peru, (See 
Fig. 2B.) 

A type of seating arrangement commonly known as continental 
seating is now* receiving some, attention. The name comes from the 
fact that this type of seating has been used extensively in Europe. 
The 1943 edition of the National Board of Fire Underwriters Build- 
ing Code and the new National Canadian Building Code permit 
such seating. Basically this calls for aisles along the side walls only 
with seats spaced farther apart for faster transverse circulation. 
Emergency exits are placed along the side walls where they are least 
objectionable. The use of floor space for seats, instead of interior 
aisles, produces a larger percentage of desirable viewing positions. 
This type of seating merits serious consideration. 19 

Now we come to a phase of motion picture theater design that deals 
with the artistic and psychological aspects which present a special and 
more elusive problem. In the motion picture theater, all of its archi- 
tecture may be optional or the product of pure art, except for the 
auditorium where the requirements for the proper presentation of the 
projected picture must be the determining factor in the design con- 
siderations. We have, subject to further refinements, developed meth- 
ods of assuring unobstructed vision and good acoustics. I think we are 
finally impressing the motion picture exhibitor with the importance of 
having an auditorium treatment subordinated and made complemen- 
tary to the picture and not an auditorium of twinkling stars and out- 

312 SCHLANGER April 

door pergolas or a replica of a French Renaissance ballroom or even 
the more modernistic decorative lines which shoot off in all direc- 
tions in all colors of the rainbow. 

What you see when you face the projected picture presents one 
problem and what you see when you leave the auditorium presents an 
entirely different problem. The latter view may well provide a 
decorative effect limited only to the discretion of the architect. The 
screen view of the auditorium, however, is one that must present a 
neutral atmosphere for the picture and therefore distracting deco- 
ration and lighting have to be avoided. Some of the care that is given 
to providing just the right frame and setting for an oil painting or still 
photograph should be given to surrounding the motion picture prop- 
erly. It might be said that our million-dollar motion picture epics 
are worthy of this consideration. 

The problem of auditorium lighting in the picture projection period 
is directly tied in with this latter problem. The light reflected from 
the screen can play an important part, in light-tinting the surfaces 
which are seen along with the projected picture. 11 Secondary light 
sources must be used with great care in the auditorium to avoid any 
distracting effect. Lighting that draws attention to iteelf draws at- 
tention away from the screen. 

We have some new fields to conquer. The cinematographic art 
and the art of presenting the film in an auditorium has to be reap- 
praised to search out new methods for increasing dramatic effective- 
ness. A co-ordinated study by the cinematographer and the audito- 
rium designer is necessary to accomplish these results. The size of de- 
tail images on the picture as now projected may be satisfactory, but 
it is possible that the picture should be larger to include more of the 
peripheral without enlarging detail images. Careful treatment of the 
peripheral is necessary to avoid distraction from the focal point of 
action. Sharp demarcation between the projected picture and its 
environs must be eliminated with even the black masking of narrow 
widths remaining a distraction. Modern projectors are capable of 
projecting a larger image but this should not be done until the audi- 
torium designer and the cinematographer learn how to use it. These 
are thoughts for the motion picture exhibitors to consider seriously if 
they would improve the art and have something more than what home 
television motion pictures will offer. 

(1) B. Schlanger, "On the relation between the shape of the projected picture, 


the areas of vision, and cinematographic technic," J. $oc. Mot. Pict. Eng., vol. 
24, pp. 402HW9; May, 1935. 

(2) B. Schlanger, "The motion picture theater shape and effective visual re- 
ception," /. Soc. Mot. Pict. Eng., vol. 26, pp. 128-135; February, 1936. 

(3) Ben Schlanger, "Applying the 'continental plan' to American theater 
seating," Better Theaters, Mot. Pict. Herald, May 30, 1936. 

(4) M. Luckiesh and F. K. Moss, "The motion picture screen as a lighting 
problem," /. Soc. Mot. Pict. Eng., vol. 26, pp. 578-591; May, 1936. 

(5) Ben Schlanger, "Motion picture theaters," Arch. Rec., pp. 17-24; Febru- 
ary, 1937. 

(6) Ben Schlanger, "Auditorium light control through surface treatment," 
Better Theaters, Mot. Pict. Herald, April 2, 1938. 

(7) B. Schlanger, "A method of enlarging the visual field of the motion pic- 
ture," J. Soc. Mot. Pict. Eng., vol. 30, pp. 503-509; May, 1938. ' 

^ (8) Theater Survey in "Report of the projection practice committee," /. Soc. 
Mot. Pict. Eng., vol. 31, pp. 480-510; July, 1938. 

(9) "Theatres cinema, community and broadcasting," Arch. Rec., pp. 96- 
128; July, 1938. 

(10) C. C. Potwin and B. Schlanger, "Coordinating acoustics and architecture 
in the design of the motion picture theatre," /. Soc. Mot. Pict. Eng., vol. 32, pp. 
156-166; February, 1939. 

(11) B. Schlanger, "Motion picture auditorium lighting," /. Soc. Mot. Pict. 
Eng., vol. 34, pp. 259-264; March, 1940. 

(12) Ben Schlanger, "Chair size and form," Better Theaters, Mot. Pict. Herald, 
June 29, 1940. 

(13) "Report of theater engineering committee," J. Soc. Mot. Pict. Eng., vol. 
38, pp. 78-81; January, 1942. . 

(14) Ben Schlanger, "How viewing angles determine the basic form of the 
auditorium," Better Theaters, Mot. Pict. Herald, p. 9, October 17, 1942. 

(15) Ben Schlanger, "Planning so patrons can see the picture, comfortably," 
Better Theaters, Mot. Pict. Herald, November 14, 1942. 

(16) Ben Schlanger, "How to use best seating areas in auditorium plans," 
Better Theaters, Mot. Pict. Herald, December 12, 1942. 

(17) Ben Schlanger, "Making seating plans meet the real needs of safety and 
comfort," Better Theaters, Mot. Pict. Herald, April 1, 1944. 

(18) Ben Schlanger, "Seating plans don't need today's code restrictions to 
make theaters safe," Better Theaters, Mot. Pict. Herald, May 27, 1944. 

(19) "The theater for motion pictures," Arch. Rec., pp. 83-102; June, 1944. 

(20) Ben Schlanger, "How function dictates an auditorium style that endures," 
Better Theaters, Mot. Pict. Herald, January 6, 1945. 

(21) Ben Schlanger, "The small motion picture theater," Arch. Rec., pp. 99- 
132; June, 1946. 

(22) Ben Schlanger, "Planning seating for comfort," Better Theaters, Mot. Pict. 
Herald, pp. 15-16; July, 26, 1947. 

(23) Ben Schlanger, "Auditorium floor slopes for motion picture theaters 
today," Better Theaters, Mot. Pict. Herald, pp. 17-18, 28; September 20, 1947. 

(24) George Schutz, "The advantages of balconies for motion picture audito- 
riums," Better Theaters, Mot. Pict. Herald, pp. 13-14; November 15, 1947. 

Theater Engineering Conference 

Introductory Session 

The Psychology of the Theater* 




Summary The motion picture theater, properly understood, has its own 
complex "psychology." This psychology must be understood in its compo- 
nent parts, and in its leading characteristics, so that all concerned may inter- 
pret it adequately. An appreciation of the mission of the theater, its activi- 
ties, and its nature, plus the nature of its relationships will aid this under- 
standing. Its place in the community will be determined finally by the 
manager's alertness, and his comprehension of the significance of the industry 
of which he is a representative. 

THE QUESTION before us is, basically, how many theater managers, 
how many members of the Society of Motion Picture Engineers, 
how many other persons connected with the industry have a signifi- 
cant conception of what we are calling "the psychology of the theater. " 
What is its meaning and significance? What is its rightful place in 
the community life? How can the character of this modern miracle 
be expressed in a personality which will walk on the same terms with 
other community enterprises? Is it possible that many persons in the 
industry, involved as they are in their own concerns, do not realize 
how really "big" this industry has become? 

All of these questions are important! A manager, if he is to be an 
effective force in his community, must know both these questions and 
their answers. It is he who must interpret the psychology of the 
theater to the community. For the theater we think has a "psy- 
chology," just as every person who comes to it has a psychology. The 
theater's personality is a complex one. It is, first and foremost, a 
business. It is often a show place in itself. It is a center of enter- 
tainment. It is an important medium of education. It is a major 
factor in shaping customs, opinions, and "behavior. It is a place of 
gathering for the community. It is, in all senses, an escape, for 

* Presented October 20, 1947, at the SMPE Convention in New York. 


through its door pass those who are for a few hours free from care, from 
problems, from the monotony and the jangling voices of everyday 

How many millions chained to one locality by circumstances, have 
passed through the theater door to the broad horizons of the wider 
world. They have sailed all the seas, have visited the capitals of the 
world, and have rubbed elbows. with distant peoples and strange cus- 
toms. The creations of artistry, the marvels of science, industrial 
processes, and travel pass across the theater screen, along with the 
explicit entertainment. Moreover and most important, the motion 
picture theater, be it in Times Square or in some remote village street, 
has become so interwoven with our modern social life that it has be- 
come indispensable. It is not too much to say that if tomorrow, 
through the operation of some almost unimaginable social cataclysm, 
every theater would be closed, on the next day there would be an 
almost universal demand for reopening! How true it is then that you 
men and women who are the stewards of the " colossal" force should 
have a real understanding of its significance. 


The individual theater is 'the outpost of the industry and the 
manager is the visible representative. For all practical purposes the 
individual theater and the manager are the industry in their com- 
munity. The manager must and should be one of the best salesmen 
of the community as well as of his product. He must never give the 
impression that he is in the community, but not of it. He should have 
sufficient latitude to enter into such community activities as will confer 
a mutual benefit on the theater and on the community. Only a 
shortsighted management would forbid him from making such con- 
tributions of time and money as will lubricate good public relations. 
The manager is there. He knows what he must do, and what he can 
refuse to do if he is to maintain good community relations. His judg- 
ment must be trusted until it is found that his judgment in such 
matters cannot be trusted. A realistic fact to be kept in mind is that 
so many people have such a vivid idea of the gigantic size of the 
motion picture industry that the idea must never get abroad that the 
theater " takes" from the community without giving something back 
along with the entertainment. 

Resourceful managers have done many different things to advance 
the legitimate cause of good human relations. They have joined 

316 CUTTER April 

service clubs. Every manager should have a membership in such 
clubs. They have co-operated in constructive community interprise^s. 
All managers should do so. Some have opened their doors for church 
services, when for some reason other quarters were not available. 
Some of the largest Sunday school classes in the country meet in 
theaters. Managers have provided the facilities, both space and 
films, for visual education of school children. Public meetings have 
been held. Other uses have been made. The underlying thought is 
not that you have to do any or every one of these, but that you should 
publish a willingness to try to meet any legitimate request. It is as 
true for theater managers as for anyone else, in the words of the poet, 
that, "What you keep is lost. What you give is forever yours!" 


Technical advances, made very largely through the laudable work 
of the Society of Motion Picture Engineers, permit the alert manager 
to exhibit another interesting facet of the personality, the psychology 
of the theater, namely, the reduction of distraction in the modern 
show. We are so prone to take inventions and innovations for granted 
that we may be unmindful of the superb physical aspect of the modern 
theater. Compare it with the early motion picture house. The 
speaker can recall the first pictures he ever saw. They were shown by 
a man who is now a leadhig exhibitor in a not too distant city. The 
" theater" was the lower floor of a dwelling house, with all partitions 
removed. The projection machine was cranked and "hot flashes" 
were frequent. A man and woman seated behind the screen "talked" 
and made sound effects. Between pictures the manager sang some 
popular song whose words, enshrined in roses, and illustrated by two 
lovers in various paralytic poses, were flashed on the screen. The 
audience helped out with the dialog. The chairs were hard. Peanuts 
and popcorn added their merry note. And the admission was five 
cents. Many of you are too young to recall that there was a time when 
five cents was a substantial medium of exchange. People went then 
because of the novelty. Few persons thought that the novelty would 

From that day to this we have come a long way in every phase of 
the theater. Technical progress in projection, sound, comfort, and 
safety has been striking. In theater architecture great advances have 
been made. While it is still recognized that a certain opulence of 
decoration is part of the theater's appeal, we have tended to move 


away from the excessively baroque and what the author terms the 
"ro-cuckoo" styles of architectural embellishments. The Idle Hour of 
yesterday would hardly recognize its modern descendant. 


But let us look at this idea which we have called the reduction of 
distraction in the theater made possible by striking engineering ad- 
vances. And it would seem that the patrons should know what under- 
lies the successful showing of a picture : Our measure of how successful 
is this reduction of distraction, is how completely the individual 
patron is enabled to concentrate on the picture without distraction by 
uncontrolled noise, faulty lighting, discomforts of any kind, or fears 
as to his safety if an emergency should come about. Continuous 
study is given to these matters by functioning committees of the 
SMPE, and theater managers have access to a wealth of technical in- 

Let us look at a few of these innovations. How many persons know 
what comprehensive study is given to theater carpet, its quality, 
texture, "joints," and method of laying. We are all greatly impressed 
by projection and sound equipment, but part of the benefits of these 
technical advances would be lost were it not for the correct pitch of 
the floor and the proper arrangement of seats. And what improve- 
ments have been made in seats and in indirect aisle lighting, in the 
skillful arrangement of gallery steps and in the marking of top or 
bottom steps whose height may differ from the others thus causing a 
tripping and falling hazard if uncorrected. Such a simple and 
effective device as the increasing width of the aisle from front to rear 
has been noticed by millions who have no conception of its sig- 
nificance in emptying a theater. 


Consider safety measures, which, though unseen to a large extent, 
must be present. The speaker is vitally interested in safety and in the 
safety of persons in places of public assembly. So are you! He is 
interested in a beautiful entrance and lobby, but more interested in 
how quickly and safely the entire theater can be evacuated. It may 
be well to repeat a statement from a previous paper: that if by reason 
of lack of provision for preventive measures a panic should happen in 
a theater, 20 years of good management can be undone in 20 seconds. 
S o we come to consider all the study that has been given to the 

318 CUTTER April 

number, the types, and the arrangement of exits, as well as the means 
which are used to inform patrons of exit locations. We are interested 
in proper lighting of outside exits, in the substitution of ramps for 
steps where possible, in the fact that all exits must lead to a safe place. 
As fire is a leading cause of panic, you, the manager, and you, the 
engineer, give constant thought to fire prevention and to the training 
of staffs in the handling of possible emergencies. A constant corre- 
spondence is going on between the manager and the engineer in which 
questions are asked and answers given as to how the safety of a given 
theater may be increased. We do not often think of this, but in pro- 
portion to the millions of patrons handled, the motion picture theater 
is relatively one of the safest places in which to be! How many people 
know this fact? All of these advances come about through the team- 
work of the engineer, and the manager, with the public as the ultimate 
beneficiary. When a patron sits in a modern theater he is enjoying, 
consciously or unconsciously, a rich inheritance of technical and 
managerial excellence. Why not tell him more about it, as the 
manager moves about the community? 


So, the manager has a great deal to sell, if he has the capacity to 
appreciate, as was said at the beginning, the real significance of that 
of which he is part. Some managers are on the defensive. They have 
an excessive deference to criticism, possibly because they are unsure 
of themselves or because they separate themselves, spiritually, from 
the producer, or, let us face it bravely, from Hollywood. That is 
rather silly, .is it not? Something like a swimmer repudiating the 
water in which he swims, saying that he would do better if he had 
different water. 

Let us look at Hollywood for a moment. Hollywood is where most 
of our pictures are made. It has been said once or twice that it is a 
rather fabulous place. Well, why would not it be? Put a large num- 
ber of creative artists such as actors and actresses, producers, direc- 
tors, and the innumerable technicians and others, all prima donnas in 
some degree, into one locality and what would you expect? Add to 
this happy company the great American vice of exploiting to the last 
degree any merchandisable commodity through every variety of 
publicity medium. Add also that army of hangers-on who make their 
fat livings battening on gossip, on unconventionalities, on shattered 


artistic reputations, so that every trivial work, happening, or opinion 
becomes inordinately magnified. If we buy a goldfish bowl and stock 
it, we shouldn't complain because thereafter we can see every move- 
ment of the fish, particularly if we have 'an announcer. An ultimate 
explanation of Hollywood doubtless never will be made, but some 
explanation that is reasonably comprehensive can be attempted. And 
it may be salutary to remember that the exhibitor would be in a 
rather curious position without Hollywood! 

Another factor which puts certain managers on the defensive is 
patron criticism of "bad" pictures. There is really little defense for 
bad pictures. We may as well be frank; some of them are pretty 
poor. Yet the wonder of it all to an uninstructed layman like the 
author is not that there is a percentage of weak pictures, but that in 
an industry which has to maintain such production schedules for so 
many different tastes, so many reasonably good ones are put out. 

What other industry of comparable scope do you know which 
within its limitations, must meet such a variety of tastes as the motion 
picture industry? The picture which nauseates the intelligentsia in 
one area, delights others. There is every possible provision for ex- 
perimental pictures, for new forms, for "art" pictures. But such 
pictures never will be commercially profitable, nor would they ever 
satisfy the majority. of tastes. Remember, this is no defense of 
mediocrity. It is a realistic appreciation of realistic problems. 

The industry must make a profit, if it is to continue to produce 
pictures for exhibition. This is something the advanced thinkers 
sometimes forget. Certainly, pictures should be better. They will 
improve slowly as writers, producers, exhibitors, and patrons improve. 
The manager can at least discuss some of these facts with the critics 
before agreeing too glibly with them and subtly conveying the im- 
pression that if he were at the helm things would be different. 

No, there is a psychology of the theater, but it is a psychology which 
must be studied constantly, and learned, and interpreted. This is no 
small activity with which you are connected. It is a "big" thing with 
magnificent opportunities and large responsibilities. It is an industry 
built on great technical proficiencies and artistic achievements. Its 
success will depend ultimately on the fullest co-operation among all 
concerned, the. producer, the engineer, the exhibitor, and the patron. 
There must be the fullest awareness of the problems just as there is 
the great appreciation of the achievements. It is the managers, 
ultimately, the men and women at the distant outposts, who are the 

320 CUTTER April 

interpreters. On this comprehension, their perception, and their 
alertness, the personality of the theater will largely depend. 

Let us take a brief journey, not to one of the great theaters in large 
cities, but to a small "house"on the streets of a town. This particular 
house is a " two-shows a night." It is dusk. As the sunlight fails, the 
twinkling lights of houses and storefronts come on. The townspeople 
are at supper. The manager of the theater stands in front for a 
moment. He' has lived here for a number of years and some of his 
roots are already deep in the life of the town. He sees lights in stores 
which would otherwise be dark were it not for the theater which 
brings the townsmen through the evening streets. He looks up and 
down the street, greets a few friends, and then passes inside. In a 
moment the bright lights of the marquee are turned on. The manager 
looks over the house, checks his little staff, and soon the patrons begin 

In this simple procedure, something really tremendous has hap- 
pened. From all of their diverse occupations, with all of their prob- 
lems, their tastes and their hopes and fears these people have come to 
be entertained. But to the manager they are not just people. They 
are his friends, his fellow townsmen. In a real sense, he is the steward 
of a wider world than these people see every day, the world of the 
cinema, both the world of make-believe and the world of reality. Like 
Aladdin, when he turns on the lights of the theater, he turns on also the 
lights, the varied lights, of human experience. Certainly there is a 
psychology of the theater, there is a personality, a meaning. 

Do we know it? 


MR. WILLIAM H. OFFENHAUSER, JR.: There is a wide variation in the psy- 
chology that you find in theaters in different places. One goes to the Music Hall 
for instance, and one enjoys the depth of the seats. I have seen pictures in the 
open down in Africa, and I can assure you the psychology of the theater there is 
quite different. When I came back, I went up to New Hampshire for a little trip 
through the White Mountains. I happened to see a picture advertised in a local 
theater which I wanted to see. It was up one flight in what is called a fire trap. 
Incidentally, it was a two-projector house, but one of them was not running. The 
audience seemed to hark back to that old gag or trick of audience reaction that 
was rather common, I think, 35 years ago, of stamping between reels. That went 
on in this small town just two weeks ago. 

Then when I come down here, we talk about a wide range of things, from what 
you might call the peak of industrial civilization as we have it here in New York, in 
the United States, and, the absence of it in some other places. 


It seems to me that the psychology of the theater extends considerably beyond 
merely the matter of mechanics and of people. It is a question of adapting the 
mechanics to the people and the people to the mechanics in some way or other. 
How it can be done, I do not know, but it does make an impression when, let us 
say, two weeks or so ago I saw, in London, one of the Hussion propaganda films in 
color, 90 minutes of so-called documentary, and then saw a film, one of our typical 
Class B minus gangster films in Africa, shown to Africans. They sit up in the 
six-penny seats. Incidentally they are interested in girly-girly shows, and all 
that sort of thing. They do not want the others. And then I saw what one might 
call a picture much closer to the Class A type I wouldn't call it quite A, probably 
B plus, in this one-projector house in the United States. It seems to me that there 
is a wide diversity of material, conditions, and equipment that is encompassed by 
the motion picture industry, and much consideration could be given to it. 

We could talk about it endlessly. But what good does it do? The reason we 
really want to come is to see a show. 

MR. BEN SCHLANGER: There is one point that Dr. Cutter brought out which 
I think is worthy of a little further enlightenment, and that is the cinema-goer who 
comes to the theater to forget all his problems completely and be in the world of 
what he is looking at in the cinema. And that is what we need greatly, a theater 
auditorium where a person can sit down and look at what is ahead of him and not 
be conscious of the physical shelter in which he is enjoying that picture. He has 
to be able to look at that picture, lose himself in it completely, and have no re- 
minder of the fact that he is in an enclosure and looking at a picture. 

That is a pretty difficult thing to accomplish but I think it is worth striving for. 

If you have auditorium walls with certain types of decorations, let us say 
Georgian and Colonial, and the picture that is being shown on the screen is a scene 
in the Sahara desert, they do not belong together at all. In other words, the 
auditorium has to be a completely neutral enclosure, to enable you to enjoy com- 
pletely that which is being shown to you, and we have to try to make that picture 
that is ahead of us not appear as a picture, but as real life; in the motion picture 
it can appear even more like real life than in the stage theater, because in Holly- 
wood the boys have a few tricks up their sleeves that can produce it. 

CHAIRMAN JAMES FRANK, JR. : The African theater, I suppose, had no walls and 
no ceiling. 

MR. SCHLANGER: You could project a picture in the open air, like in a drive-in 
theater, and you will have this: a very brightly lighted picture, and then the black 
of night around you. That is a little better than sitting in an enclosed theater 
with a bright screen and many other distractions, but there is still another point. 
You have to go even further than that. You have to accept the shelter that en- 
closes you in an indoor theater and take advantage of the shelter and use the sur- 
faces of that shelter to create a light tint which will be related to the picture in- 
stead of having a black surrounding around the picture, which is an artificial 
masking. We do not walk around all day long with a black frame in front of us 

Theater Engineering Conference 

Physical Construction 

General Theater Construction* 


Summary This paper will discuss the uses of alternate materials and 
to some extent the varied requirements to be considered in the construction 
of a modest or low-cost type of theater as compared to the construction of the 
more elaborate or so-called de luxe motion picture house. It will neglect 
the considerations of the special features such as layout of a full-act stage, 
stage lifts, gridiron, dressing rooms, paint bridges, orchestra lifts, and other 
requirements of a full presentation or legitimate theater, as probably there 
will be few theaters of this description constructed in the immediate future. 


WHEN CONSIDERING the construction of a theater of any type, it 
might be in order to mention that the estimates received at the 
present time, for the building of a proposed low-cost or modest house, 
take on the proportions of a de luxe theater; surely ijie prospective 
owners sincerely believe that the architect has included a fully 
equipped stage, solid-gold hardware, and mink-lined cosmetic rooms. 
However the prospects of a substantial reduction in the cost of 
theater building and theater equipment in the near future, are, in the 
author's opinion, not at all promising. 

The matter of location of the theater, the accessibility to transpor- 
tation, parking facilities, orientation of entrance features and mar- 
quees, vertical signs and similar questions will be discussed in detail by 
others, and therefore these topics, which of course are of primary im- 
portance, will be left for future consideration. 

The more important functional and esthetic elements necessary in 
a good motion picture theater of both the modest and de luxe house, 
will be discussed in more or less the sequence of importance in which 
they affect and influence the average theater patron. Many will no 
doubt disagree with the order of presentation, but the theater patron 
will not be concerned with the sequence so long as all elements in one 
form or another are present. All are vitally important and necessary 
* Presented October 20, 1947, at the SMPE Convention in New York. 


in the construction of a new theater; the functional elements to a far 
greater degree than the esthetic, which however, cannot entirely be 
neglected, in any theater. 

Disregarding in this consideration such important requisites as 
cleanliness and courteous service, the following elements seem most 
vital and necessary : 

1. Comfort while watching the show. 

2. Good vision of the picture and proper projection. 

3. Good sound. 

4. Adequate and inviting toilet and rest-room facilities. 

5. Ample and properly arranged lounge and circulating spaces. 

6. Pleasing and attractive interior architectural treatment. 

7. Attractive entrance and exterior treatment. 

8. The physical structure of building. 


Under the first heading several factors will be considered, which 
will cause the patron to feel comfortable. Starting with the seats 
there is, of course, a wide range in both comfort and cost; however 
even the modest theater should have spring seats with upholstered 
backs of 20-inch minimum width, and spaced not less than 2 feet and 
10 inches back to back of seats. The covering may be of leatherette, 
corduroy, mohair, or other serviceable material. In the de luxe the- 
aters the covering materials would be of better quality, the seats and 
back upholstering would be deeper and more luxurious even to the ex- 
tent of providing foam-rubber and upholstered arm rests, the seats 
should .be 21 to 23 inches in width and back-to-back spacing from 3 
feet to 3 feet 3 inches. Loge seats should be at least 22 inches wide 
and spaced not less than 3 feet 4 inches back to back. Orchestra 
rows 3 feet back to back with 2 1-inch- wide seats would be a good 
average for acceptable comfort. 

The next consideration is "ventilation." Here again even the less- 
expensive theater must have adequate ventilation, without annoying 
or noticeable drafts. All theaters, where the hot summer season is 
of considerable duration, should be air-conditioned, at least pro- 
visions should be made in the ventilating system and layout of the fan 
room, so that cooling coils and refrigerating equipment, either for well 
water or compressor, could be installed in the future. If ventilation 
alone is installed the author recommends 35 to 50 cubic feet per min- 
ute of air per person; if well water is used, 30 cubic feet per minute 

324 MCNAMARA April 

would be sufficient ; and if cooling is obtained by means of compres- 
sors 20 to 25 cubic feet per minute per person should be provided. 
In the smaller inexpensive theater, where air conditioning cannot be 
provided, the ventilation may consist simply of large quantities of air 
with no return or recirculating ducts or trenches under the floor. In 
the better theaters return air ducts or trenches would be built under 
the orchestra floor, located in relation to sources of air supply; to pro- 
vide even ventilation in all parts of the house. 

A separate smoke-exhaust system should be installed wherever the 
budget permits; this should be a definite requirement for a de luxe 

In connection with recirculating ventilation systems there has re- 
cently been considerable discussion concerning automatic electric 
shutoff equipment on main fans by New York State Authorities; 
however, the author believes that a manually operated shutoff switch 
controlling the main supply fan could be provided in a readily ac- 
cessible location in the auditorium, outside the fan room, and this 
would prove more practical in preventing the speed of smoke through 
the theater in case of fire. 

A third element which vitally affects the comfort of patrons is the 
lighting of the auditorium, while the picture is on. In all theaters the 
amount of exposed lights, lighted wall, or ceiling surfaces above the 
patrons eye line should be reduced to a minimum. A major portion 
of light required in the auditorium can be obtained by providing a 
relatively brightly lighted aisle by means of closely spaced aisle lights. 
There should be no exposed bulb lighting on either walls or ceiling 
that might be a distraction. 


The second fundamental features are good vision and projection. 
These are essential in all theaters in very much the same degree. 

Good projection depends primarily on good projection equipment 
located in the projection booth as close to the center line of the screen 
as practical, and with as flat a projection angle as possible, together 
with a good screen of the correct size for the length of the theater. 

Good vision will depend on a good sight line with sufficient slope or 
proper grading of the orchestra floor, arid proper stepping arrange- 
ment in the balcony. The sweep and staggering of seats, the arrange- 
ment of aisles and crossovers and vision angles at front rows will also 
greatly affect the proper vision of the picture. This might be the best 


time to discuss briefly the projection-booth layout. In the theaters 
with a very low budget the booth should be arranged for two active 
machines straddling the axis line, and also space for one additional ma- 
chine as well as room adjacent to one side wall, on which the control 
panel for all house lights should be located. A rewind room even 
though it be small, should be arranged adjacent to the booth with 
vision ports permitting a view of both the screen and projection ma- 
chines, while the film is being rewound. A generator or rectifier 
room is essential as well as a toilet room for the operator located as 
close to the booth as possible. 

In the booth for the better theaters, there should be three projection 
machines, one spot machine, and space for a future machine or piece of 
equipment which may be required for television or other new projec- 
tion equipment. This type of theater should have house lighting on 
dimmers and wall space should be provided for light panels and dim- 
mer banks in the booth. A vision port should be provided through 
the front wall adjacent to the light panel. The upper walls and ceil- 
ing of the booth in a de luxe theater should be acoustically treated 
with fireproof acoustical tile or perforated transite board. There 
should also be a film lift provided from the street-level floor to the 
booth . This feature might be eliminated in a very inexpensive house . 


Good sound first requires good sound equipment in the booth and 
at the screen. This is also a fundamental requirement in all sizes and 
grades of theaters. Good sound also will depend a great deal on the 
acoustics of the auditorium. In all theaters the acoustics can be con- 
trolled by he use of various acoustical materials on the walls and 
ceilings; by the shape of the auditorium; by the arrangements of 
forms and movement of the wall and ceiling surfaces; by the volume 
or cubical content of the auditorium ; by the size and shape of the bal- 
cony; and also by the upholstery on the seats and the floor covering. 
. In the low-budget theater a great deal can be accomplished by the 
use of highly absorbent materials on the few acoustically vital wall 
surfaces, and by shaping or sloping other walls in relatively inexpen- 
sive materials. 

In the more-expensive type of theaters architectural embellish- 
ments can be used in forms and designs that will be decorative and 
also add to the acoustic properties of the auditorium. (Theater 
acoustics will be covered by other papers.) 

326 MCNAMARA April 


The next consideration will be ample and inviting toilet and rest-room 
facilities. The location of the toilet rooms is most important. They 
should be readily accessible to all patrons with a minimum of travel 
and cross traffic. The necessity of having patrons use stairways to 
lounge and toilet rooms should be avoided whenever possible. There 
should be sufficient fixtures provided in all types of theaters ; in smaller 
and less elaborate theaters, the proportion should be not less than 
one fixture for each 100 patrons, and in the better theaters the ratio 
should be not less than one fixture for each 75 patrons. In all toilet 
rooms the floors and wall wainscot to a minimum height of 5 feet 
should be of an impervious, easily washed material. 

In the less-expensive theater the floors and base could be of tile or 
terrazzo, the toilet stalls of flush baked-enamel steel. The walls may 
be covered with tile, terrazzo, asphalt tile, linoleum, or composition 
tile. In the de luxe house the floors and base may be of tile or terrazzo 
or marble. The walls of structural glass, glass mosaic, tile, terrazzo, 
marble, or formica should have a minimum height of 6 feet and 
preferably extend to the ceiling'. Remaining plaster surfaces should 
have a flat enamelled finish or they could be covered with washable 
wall paper. Toilet stalls for better theaters should be of structural 
glass, marble, tile, or porcelain-finished steel partitions, hung from 
ceiling supports. Wherever the budget will permit, all plumbing fix- 
tures should be hung from the wall to facilitate frequent washing of 
the floors. 

In all new theaters there should be cosmetic or anterooms of varying 
sizes leading to the ladies' toilet room. A men's smoking room need 
be provided only in de luxe theaters, in all others an entry space only, 
sufficient to provide privacy, is required. 


Lounge space will vary in location, size, and shape in practically all 
theaters. In the smaller inexpensive house the orchestra promenade 
should be of ample size but the lounging space can be reduced to a 
minimum. In the larger and better theaters there should be large 
lounging and circulating areas provided, preferably near the rest rooms, 
arranged, however, so that the noises from the lounge will not be 
audible to people watching the show. In the de luxe theaters there 
will be a check room, a room for lost and found articles, also a so-called 


crying room for infants, preferably with a window at which the parent 
may watch the picture while sitting with the child. 

The manager's office should be located near the orchestra prome- 
nade, and, where finances permit, a toilet room, clothes closet, ticket 
closet, and built-in safe should be provided in the manager's office. 


Pleasing and attractive interior treatment applies to the promenade, 
foyer, and lounge areas, toilet room, as well as the auditorium. The 
interior architecture will be influenced by the money available for 
such treatment and also the ingenuity, designing skill, and taste of the 
architect, from whom, as is well known almost anything or everything 
can be expected. 

In the inexpensive theaters pleasing effects can be obtained by 
grouping a few very simple attractive shapes and by changing the 
planes and directions of walls and ceiling, concentrating the interest 
at the stage or some special motif of design. 

In the de luxe theater there will be greater latitude possible by using 
marble, real wood, mirrors, indirect lighting, run-plaster molds, and 
occasional cast-plaster features ; most of which must be omitted to a 
great extent in the inexpensive theater. 

More neon and cold-cathode lighting will be used in new theaters of 
the better type, but the cost will restrict to some extent the use of this 
type of lighting in the cheaper houses. 


An attractive entrance and exterior treatment are most important in 
all types and sizes of theaters, and particularly so in locations in which 
competition and transient patronage are essential .considerations. 

Even in the theater in which every dollar invested must be made 
apparent, it is good showmanship and good business to spend just a 
little more on an attractiye and inviting exterior entrance treatment. 

Instead of the scarce theater materials such as brick, tile, structural 
glass, terrazzo, and formica, stucco and aluminited aluminum can be 
used in interesting forms and colors. Here very high light intensity 
is a primary requisite. 

In the better theaters, the use of materials such as marble, lime- 
stone, glass, mosaic, tile, granite, and terrazzo in conjunction with 
stainless steel or bronze will provide the opportunity for a more elabo- 
rate and diversified entrance treatment. 


The box office should be outside of the first set of doors even in 
locations in which inclement weather is a serious consideration. It 
should be located to provide the best shelter for patrons under the 
marquee or canopy and also should be visible at the first sight of the 
theater entrance. 

Structural. glass doors probably should be used in the more-expen- 
sive theater, whereas, aluminum, formica, or natural wood doors could 
be used in the less-expensive house. 


We are all searching for some new and less-expensive materials or 
methods of erecting the known materials, so that more theaters can be 
built at lower costs. The details of the light-steel frame and exterior 
theater, as well as the wood frame and wood-exterior theater, will be 
presented in other papers. This article will cover briefly other types 
of construction. 

For the inexpensive theater, it probably will be found that a build- 
ing constructed with brick side-wall piers to support roof trusses, 
which jnay be of either wood or steel, and walls of cement or cinder 
block, would cost the least at the present time. The blocks may be 
painted with water-resisting paint, or stucco may be applied which will 
stand up very well in the more moderate climates. The entrance 
features may be embellished by the use of aluminum, porcelain, en- 
amelled steel, or brick. The better construction for most locations 
in this country but more costly, of course, is skeleton steel frame for 
walls and roof, walls faced with brick and backed up with masonry 
block, and the roof of lightweight masonry plank, such as gypsum or 
porete support on steel. 

In some locations in this country and in a great many foreign and 
South American countries reinforced concrete construction is used 
almost exclusively with excellent results. Very often steel is used for 
the roof trusses only. With lumber at its present high cost, the 
tendency, even in small theaters, is to use more fire-resistant materials 
throughout the theater, particularly in roof construction. 


This subject is, as will no doubt be realized, limitless in its scope and 
there are so many special types of theaters, such as the first-run, high- 
admission house, the very small village and neighborhood theater, 
and on the other hand, the very large and showcase theater,, that it 
has been impossible to discuss it all in the space allowed. 

Theater Engineering Conference 

Physical Construction 

Influence of West Coast Designers 
on the Modern Theater* 



Summary The influence of the motion picture studios on West Coast 
motion picture theater architecture is described. The typical present-day 
motion picture theater of West Coast design is discussed. 

ON THE WEST COAST there is a point of view on theaters which may 
not be superior to any -other part of the country, or the world, 
but which has been influenced by the ideas and desires of the people 
who make motion pictures. Being close to the motion picture studios 
we are guided a great deal by what the producers, directors, cinema- 
tographers, and other creative artists say at the time their pictures are 
being screened in the theaters. They often come into our office to 
present their observations and we have from time to time used de- 
signers from the studios who attack the problem strictly from the 
standpoint of showmanship and not from the staid architectural 
school. This has presented a rather free idea. We have developed 
the point. of view that perhaps all of the things we were taught in ar- 
chitectural school were not the essentials of the motion picture theater. 
The entrepreneur of .the motion picture is attempting to create an 
illusion of reality, not reality itself, but a series of plausible situations 
which are interesting, exciting, and which provide the audience with a 
means of escape from the monotony of everyday existence. During 
the time the picture is being screened he does not want the possible 
distracting influence of illuminated interior decorations no matter how 
beautiful they may be, or of any other light or sound effect that might 
compete with the picture interest. He is in complete agreement that 
the motion picture theater should be an attractive showcase for his 
product; however, he will vigorously oppose anything that might in- 
terfere with the illusion he has created. 

* Presented October 20, 1947, at the SMPE Convention in New York. 


330 LEE April 

The importance of our designs of interest in this paper begins and 
ends with the typical present-day motion picture theater operation. 
This type of design took hold on the West Coast about 1935 and the 
pattern is continuing at the present time. 

The Academy Theater which we constructed in Inglewood, Califor- 
nia (Fig. 1), is an outstanding example of advancements made in 

Fig. 1 Academy Theater, Inglewood, California. 

theater design on the West Coast. As the patron approaches this 
theater, a slender round tower 130 feet high attracts his attention. A 
spiral relief resembling a ramp carries a triple column of color-chang- 
ing light which ends at the top in a scintillating ball of neon. The 
front and back of the tower displays the name of the theater in neon- 
outlined letters while the two sides support the word "preview" in 
neon, which is only visible when the tubing is illuminated at night. 
The parking lot with an entrance at the left of the theater allows 




the passengers to alight on the same side as the box office. Angular 
designs in the ornamental sidewalks of terrazzo suggest an approach 
to the streamlined box office of white metal. Translucent plastic 
letters announce the current pictures on the front and two sides of the 
marquee and the marquee soffit is studded with reflector-type incan- 
descent bulbs and neon tubing in modern form. By the time the 
patron has passed through the wide lobby and glanced at the free- 
standing poster cases, he has been taken out of his everyday 

Fig. 2 Black-light illumination in Academy Theater. 

atmosphere into one of entertainment psychology. He is now better 
prepared to see the show inside. 

The lobby reflects the conscious study to be modern without being 
severe. We do not believe the theater patron of today will enjoy an 
atmosphere of severe modernism devoid of surface ornament. The 
ornament should, however, be well placed and lean toward the unusual. 

We believe that one of our outstanding contributions to modern 
motion picture theater design is what we term the "light trap." We 
have long recognized that extraneous light flashing across the screen 




has been a barrier to good operation. This light, of course, appears 
froin the foyer when a door at the end of the aisle is opened to admit 
patrons. In order to eliminate it we designed the light trap, a very 
simple device created by turning the doors at right angles to the 
screen. Consequently the light from .the foyer will never enter into 
an aisle to distract attention from the screen. Some capacity is lost 
in gaining this end; however, we have found it well worth the sacrifice. 
We believe that this theater is the first one in which a major experi- 
ment was made in the use of black light (Fig. 2). The coves in the 

Fig. 3 Tumbleweed Theater, Five Points, California. 

ceiling are designed to take dimmer-controlled neon lighting and in 
these same coves we have placed black-light sources. The wall 
decorations have been painted with fluorescent paint, and many 
combinations of neon and fluorescent colorings are available The 
producers object to the use of fluorescent colorings during the time 
the picture, particularly one in color, is being screened, but inasmuch 
as the lighting may be controlled from the projection room it is only 
used when it is effective. The aisle carpet also is fluorescent and is 
illuminated with black light which aids greatly in seating. These 


lighting units are .placed at the aisle seats. Attempts were made to 
illuminate the aisle carpet from overhead, but the light reflected from 
eyeglasses was disturbing to the wearers of glasses. 

We have used black-light decorations in many of our houses and 
found that lamp replacement offers a major problem to the operator. 
This may be due to the intervening war years in which these lamps 
were not available and while we built the first fluorescent-lighted 
theater in 1939 and several in Mexico in 1941, the black light was un- 
available chiefly during the war years and our experience record is in- 
complete on this item. 

We have built some very low cost theaters on the West Coast that 
have been extremely interesting and well-paying ventures (Fig. 3). 
Outstanding is probably the Tumbleweed Theater, Five Points, 
California, which we designed for the Edwards Circuit and which was 
built at a cost of $30.00 per seat. 

Having the problem of a small country area and a rural community 
the owner of this theater stated he would like to have a barn in which 
to put pictures. So the building sits back from the street with a 
barnyard in front wfiich contains a wishing well, an old oaken bucket, 
and cast-plaster ducks and ducklings. Search was instituted for an 
abandoned windmill, and this was erected on a pump tower, operated 
by an electric motor, and is a landmark for miles about. 

The marquee was built around the base of the mill tower, with a 
box office below, and forms the main entrance. Poster cases alter- 
nating with old wagon wheels, also the product of an entertaining 
search, form the fence for the yard. Gay farm colors of white, yellow, 
and blue with red wagon-wheel spokes make the exterior bright and 
cheery. The ranch atmosphere is carried out inside the theater by a 
foyer treated as the living room of a farm home. Papered walls with 
early American furniture make this appear authentic. 

The auditorium has a ceiling formed by the roof trusses as barn 
beams would appear. Lighting fixtures are wagon wheels, three 
colors of lights being used in the glass rims of the wheels. Walls have 
appliques of western rural ornaments. An interesting note is the 
fact that the chimney on the front of the building is used as a port for 
the ventilating system, fresh air being introduced into the front of the 
building and removed from the rear. 

Our West Coast office has also had some interesting experiences in 
connection with food operations in the theater. This lucrative ad- 
dition, which started as a folding candy and popcorn dispenser, has 




developed into elaborate concessions which include soft drinks. We 
have even had proposed records, sheet music, and greeting cards. 

In Mexico we were privileged to design a few theaters where we 
entered into the full impact of concessions in the theater. The show- 
going habits in that territory were affected by the siesta period fol- 
lowing which the th'eaters opened, usually around four o'clock in the 
afternoon, and considerable food was sold in the building. We, there- 
fore, developed full-sized food concessions, usually consisting of a 
large room off the main lobby. 

Fig. 4 Integral design of restaurant and theater fronts, Miami Theater, 
Miami, Florida. 

In the Linda Vista Theater at Mexico City we provided two food 
departments, one directly off the main lobby for the service of sand- 
wiches and the other connecting with the building and occupying a 
common patio with the theater for full food operation. The food con- 
cession inside the theater also handled candy, and serving light 
lunches and coffee, did a steady business. 

One parallel operation in the United States is the Miami Theater, 
Miami, Florida (Fig. 4), which our West Coast office designed. 
Built on the main street of the city, it has a combination Huyler's 


candy store and restaurant in conjunction with the theater. We ac- 
complished the dual operation by having the candy department on the 
foyer floor open directly from the candy store to the foyer. Outside, 
the doors lead from the candy store to the box office, or from the street 
to the candy store, and we designed the mezzanine level of the theater 
to be the second-floor level of the restaurant. Service for candy 
and drinks operates on either the theater side or the luncheon side and 
there is direct access from the mezzanine of the theater to the restaurant. 
Having the appearance of one operation, the flow of traffic is easily 
attracted from one to the other. The way the doors are arranged 
there are no serious problems in handling pass-out checks. The only 
construction problem encountered was the requirement of a fire wall 

Fig. 5 Model of precut-principle theater. 

with fire doors between the two units. This was easily accomplished 
by handling our construction architecture accordingly. 

The basement contains the entire kitchen facilities and food on 
the various levels is handled by dumbwaiters. The entire front of 
this building does not separate the theater and food departments 
except for the marquee and although the front portion of the second 
floor is entirely occupied by the food department, the outside ap- 
pearance indicates that the theater uses the entire upper area. 

We believe that the West Coast was one of the first areas to adopt 
large parking spaces for automobiles. Some areas potentially are on 
wheels and practically every patron arrives by motorcar. We 
started building 'large areas behind the theaters for accommodating 
the patrons and attempted to make the automobile park an integral 
part of the theater by having the park entrance directly under the 

336 LEE 

marquee and located so that passengers may alight as near the box 
office as possible while the driver, or attendant, parks the car. 

Fig. 5 shows a successful design effort in what we believe is an an- 
swer to the complication of present-day low-cost theater construction. 
This is not a de luxe operation, it cannot be used in every situation, 
and it will be controlled somewhat by fire ordinances. It was de- 
signed first for Latin America and then applied to the United States. 
In the illustration shown the auditorium was left above ground level 
because of a high water table. Where the high water table does not 
exist we drop the stairs and start our construction two ways; one 
from the ground and the other by having the walls six or seven feet 
above the ground. This is not a prefabricated idea but is somewhat 
a precut principle. 

We simplified all of the elements that go into general construction 
of the building and constructed the roof out of a proportioned wood 
system and the exterior covering is in interlocking aluminum. For 
the oramental feature, a tower was designed of aluminum pipes 
played upon by. floodlights of different colors. Several of these proj- 
ects are in construction and while they are still semiexperimental 
from a cost standpoint, we believe that our construction cost will be 
in the neighborhood of $75.00 per seat." 

Theater Engineering Conference 

Physical Construction 

The Drive-In Theater* 



Summary The problems involved in planning and building a drive-in 
theater are outlined. The following topics are treated: selection of the site, 
grading, drainage, and traffic control. Also considered are the proper eleva- 
tion of ramps, lighting, and landscaping. 

ONCE AGAIN through the medium of invention, through its ability 
to reach more people, the influence and power of the motion pic- 
ture industry is expanded. 

With the advent of the Hollingshead Patent the drive-in motion 
picture came into being. It became possible for a whole group of 
people to attend the pictures, who previously could not, or preferred 
not, for one reason or another. In this class are invalids, their care- 
takers, parents with no one to mind their young children, and many 
others to whom the comforts of home mean more than seeing Betty 
Grable. Now the comforts of home can be taken right into a drive-in 
theater. Any drive-in manager has had the thrill of meeting crippled 
or otherwise handicapped people who, as a result of the drive-in are 
seeing their first motion picture in years, if not their first motion picture. 

The drive-in theaters are so large that economical construction de- 
mands an engineering approach to many of the problems encountered. 
These are first a site problem; second, an earth-moving or grading 
problem; third, a drainage problem; fourth, a structural problem; 
and fifth, a traffic problem. 

The site problem is often difficult to solve, particularly in moun- 
tainous or rolling country. The problem is, of course, to find a 
sufficiently large area within easy rea*ch of a center of population. 
This cannot be just any land. The topography must be such that a 
theater can be constructed without too great cost. 

The grading cost can be very critical. A drive-in theater of 660- 
car capacity covers approximately eight acres. Just one inch in 
height over an area of eight acres amounts to a thousand cubic yards. 

* Presented October 20, 1948, at the SMPE Convention in New York. 





From this it is understandable that just any plot will not do. How- 
ever, a variety of different topographies can be accommodated. 

The ground can slope toward the screen but preferably at not a 
greater slope than four feet in 100. It may slope away from the 
screen but preferably at no greater slope than three feet in 100. It 
may slope from one side of the theater to the other but preferably at 
no greater slope than five feet in 100, and the side slope of the finished 
theater should not be greater than 4 per cent or discomfort will be 
experienced by those sitting on the slanted surface. Naturally the 

Fig. 1 Photograph taken through the windshield from the rear seat with 
the car parked in the second ramp. 

car will slant sideways at the side pitch of the theater. We like to 
hold this pitch to 3 l / 2 per cent or less. We have gone to 4 per cent in 
one or two cases. 

This takes us into the grading problem. Each car must be posi- 
tioned so that its occupants can see the screen. The people in each 
succeeding row must be able to see over those in the preceding row. 
(This art is taught by the Hollingshead patent.) Rear-seat vision 
must be obtained at least from the third ramp rearward. The first 
two ramps can be filled by cars having only front-seat occupants. 

Adequate vision, particularly from the rear seat, requires that the 




car be tilted or aimed toward the center of the screen. This is very 
important since with the large screens used, practically the whole 
windshield is filled with the picture. Naturally if the car were not 
aimed at the picture, the top.or bottom of the picture would be cut off. 
How critical this is, is shown by the fact that even in the second ramp 
of a large theater, at a point 173 feet from the screen, it is impossible 
to see the entire height of the picture through' the windshield from a 
rear seat. Fig. 1 illustrates this. Fig. 2 shows that in the third ramp 
the screen becomes fully visible from the rear seat. The usual wind- 
shield height is 12 to 14 inches. 

Fig. 2 Same view, with car parked in third ramp. 

The front of the car is elevated for the aiming operation by use of a 
ramp and the operator can control the angle of the car by the distance 
he drives up the ramp. It is not enough, however, just to throw up a 
series of ramps and allow the driver to choose his pitch by the distance 
he drives. The occupants of each row must be able to see the bottom 
of the picture over the preceding row. This involves the correct 
relationship between the elevations of the ramps. We must go as 
high with each succeeding ramp as needed to accomplish this purpose, 
but no higher than necessary or we increase grading costs and compli- 
cate the drainage problem. 

The calculation of the elevations of such a system of ramps is 




relatively simple, but just one system will not do. We must have a 
large number of systems to fit the various topographies selected, and 
so avoid excessive earthwork cost. The different systems are obtained 
by varying the height of the screen. The higher the screen the lower 
the ramp system related to it. A one-foot jump in the height of 
the screen will lower the necessary elevation of the rear ramp three feet 
or more, depending on the number of ramps. 

We can then select the system of ramps which best fits our site, 
and adjust its height to balance cuts and fills. This produces the 

Fig. 3 All-steel screen in North Jersey theater. 


Note man standing at the 

least amount of earthwork and allows the grading to be done by a 
short-haul "put-and-take" method. This is the type of grading that 
can be done very cheaply by bulldozers or carryalls. 

Side pitch of the theater must be set at not less than 0.4 per cent 
and not more than the 4 per cent previously referred to. We may 
drain from the center to both sides or across the theater from one side 
to the other, depending upon the topography of the site and the drain- 
age conditions. 

Balancing earthwork means that we must cut into the existing 
ground surface at least a couple of feet at the low point. If drainage 
cannot be had from this elevation, it may be necessary to grade the 




theater by bringing in fill from outside. This fill method is expensive, 
however, and increases the earthwork, in the case of an entire fill job, 
approximately fourfold. This is why sites that .require fill, either 
from a drainage or a stable-soil standpoint, are expensive to convert 
into drive-in theaters. 

If the ground does not slope away from the theater sufficiently, 
drainage often can be obtained by ditching or piping to roadside 
ditches or near-by streams. It is very important that the topography 
show these drainage possibilities. 

Fig. 4 General view of same theater. 

Our structural problem mainly is in the screen. These run from a 
minimum of 35 by 45 feet to a maximum of 53 by 72 feet. The dis- 
tance of the bottom of the screen from the ground is usually 18 to 22 
feet. So in the case of the large screen, the top is approximately 75 
feet off the ground ; this is a structural problem of the first magnitude. 

We are separating this problem from others by keeping all other 
buildings as separate structures. We believe this to be the most 
economical approach. This makes the screen a sort of special and 
glorified signboard. We believe in keeping it as simple as possible 
and merging it with the ground by proper landscaping. A number of 
interesting shapes are coming out of this conception. One of them is 

342 TAYLOR April 

illustrated in Fig. 3. A general view of the same theater is shown in 
Fig. 4. The open space at the bottom of the screen will be closed by a 
planting of shrubs, and small trees. 

The special structural problems of the projection and concession 
booths is to construct so as to occupy as little total height as possible. 
Too high a structure ruins parking in too many ramps at the rear of 
the theater. This dictates thin roofs placed at exactly the correct 
elevation. The roof should slant from front to back a proper amount 
to take advantage of all the height possible. In our designs, we fix 
these roof slants to give vision in the second row back of the booth. 

A drive-in theater will need, of course, rest rooms and a ticket booth 
or booths. The rest rooms usually are placed in the projection build- 
ing because it is somewhere near the theater center. The placing of 
the ticket booth brings us to our traffic problems. 

The ticket booth should be placed in a wide driveway at least 
several hundred feet from the highway. In this way the driveway 
area on the street side is available for storage. Failure to provide 
this storage will result in a^back-up of traffic on the highway and a re- 
sultant irritation of local and sate traffic authorities. The amount of 
storage needed depends on the size and business of the theater. 

The back-up occurs when the theater is originally loading and also 
when it is full and patrons are waiting for the show to change. At 
one North Jersey theater, the number of these waiting patrons re- 
sulted in a two-mile back-up on the highway. The solution was 
simple; a parking lot with a capacity of four to five hundred cars 
properly located so that vehicles could easily get into it from the en- 
trance drive and easily out of it to the ticket booth. These parking 
lots are being incorporated into several large theaters under con- 
struction in this area, and are being added to some already built. 

No mention has been made of the electrical problem. The in-car 
speakers require electric cable. This is usually sunk in the ground 
10 to 12 inches and the speaker stands connected to it. These stands 
are 18 feet apart to allow for the parking of two cars between them. 

The .entrance and exit driveways should be lighted as well as the 
parking lot, if one exists. It is customary to mark the ramps at the 
sides and center of the theater with concrete posts on which are 
painted and illuminated the numbers of the ramps. The illumination 
is accomplished with a simple fixture which throws the light down- 
ward on the number. The numbers are placed on both sides of the 
post. They are needed to guide patrons back to their cars after 




visiting rest rooms and concession booths. As the rear ramp in 
many theaters is 600 feet from the screen it is evident people need 
something to assist them to~find their cars if they have left them. 

A novel feature at a North Jersey theater is a hundred-foot pole at 
the rear of the theater, on the top of which are erected floodlights to 
bathe the theater in soft moonlight. On moonlight nights the arti- 
ficial product is not used. 

Landscaping is an important part of all 'drive-in theaters. The 
actual selection of materials to be used is left to the local owner. It is 

Fig. 5 A parking lot for a New^ Jersey theater. 

presumed that he will use those materials best suited to his particular 
locality. (See Fig. 5.) 

When Hollingshead conceived the idea of the drive-in theater, dur- 
ing the depression years, he said that he thought in terms of the 
things that the majority of people would give up last. He decided 
the two top items were automobiles and motion pictures He put 
them together through his ingenious invention, and we have the drive- 
in theater. How good his judgment was is attested by the large num- 
ber of theaters already in use. The experimental stage of the drive- 
in is past. It is here to stay as an ever-growing factor in the industry. 

Theater Engineering Conference 

Physical Construction 

Foreign Theater Operation* 



Summary The theater situation in Australia is treated extensively in this 
paper and building problems in Egypt and in Peru are outlined briefly. It 
is pointed out that the rest of the world looks to America for the latest inno- 
vations in theater construction and equipment. 

No MATTER where one goes in this world, people in general are 
much the same. They all have the same impulses as ourselves, 
like to live well, look well, eat well, and have all the luxuries possible, 
all of course governed by local custom and supply. 

In Australia, the people are perhaps more like Americans than any- 
where else in the world. They are gracious, hospitable, and great 
movie fans as well as motion picture builders and operators. The 
Australian theaters, in general, are large, well constructed, well de- 
signed from sight lines as well as acoustically. It is not unusual to 
find 3000 to 4000 seats in even the neighborhood houses. They are 
usually constructed of reinforced concrete, of modern design with 
beautiful patios surrounding their lobbies; the walls are of plaster and 
the acoustical materials well thought out in design, with indirect 
lighting. . The foyers and aisles are usually carpeted 'and a real de 
luxe form of decoration is used throughout. Some theaters even 
were carpeted under all seats. 

During the recent global war (which physically crossed Australian 
shores) their theaters were kept in operation. It is true, replacements 
were hard to obtain, but they did a splendid job and even now, with 
replacements still very difficult to acquire, they have kept and main- 
tained their theaters in excellent condition. 

Throughout Australia the fire and safety regulations are similar to 
ours. Only in rare situations can one find a theater with poor exit 

* Presented October 20, 1948, at the SMPE Convention in New York. 


facilities. However, their fire-alarm systems, particularly in Adelaide, 
the capital of South Australia, far surpass ours. There they have the 
latest type of warning system thoughout the city. In each place of 
business and on street corners where a fire-alarm box is stationed 
a loudspeaker microphone is built into the box which is hooked directly 
into the nearest fire station. 

In the rear of the Paramount branch office, right by the film vaults, 
one of these fire-alarm boxes was on the wall. We pushed a button 
and within a second a voice came back over the loudspeaker from the 
fire station: "What's the matter, Paramount what's wrong?" 
This enables one immediately to tell the Fire Department how serious 
the fire is, and the type of fire that it is. This method gives the Fire 
Department the opportunity of telling how to fight it and exactly what 
to do. In turn, the Fire Department knows exactly what type of 
apparatus to send out. This system is also hooked on to the sprinkler 
system, so that should a sprinkler go off it causes a flash in the main 
fire station the minute the circuit is broken, you hear a voice coming 
over that same speaker saying, "What's the matter, Paramount?" 
"In this case, should no one answer, certain apparatus is dispatched 
immediately. Should a fire break out and one be unable to remain 
near the fire box, they can speak to you over this microphone from a 
distance of better than a hundred feet. 

At the fire station, in order to demonstrate the qualities of the 
system, a button was pushed which sounded in the rear of a theater. 
A voice came back, asking the Fire Department what was wanted. 
The fireman said an American was looking over the system and he 
wanted to show how it operated. Whereupon the fireman turned more 
power on the microphone and the voices of the actors from the screen 
could be heard. It was pointed out that a large fire, which most 
probably would have caused extensive loss of life and millions of 
dollars in damage, recently was prevented, due to this alarm system, 
as the Fire Deparment was able to tell the people turning in the 
alarm how to fight the fire until such time as the equipment arrived. 

This system is also used throughout the streets of Adelaide and 
many lives have been saved pedestrians as well as firemen by not 
having to send out full equipment. When an automobile is on fire, a 
person can go to the box at the corner, push the button, and report 
the extent of the fire, and adequate rather than full equipment is sent 

False alarms are prevented because if someone rings the alarm and 

346 CRYSTAL April 

is asked, " What's the matter?" and the person does not say what is 
wrong, the fire station immediately turns the amplifier on full, so that 
the fireman's voice will reach blocks away throughout the neighbor- 
hood, with the control officer at the fire station calling out, " Catch the 
person who turned on the alarm!" In this way, the Fire Department 
is prevented from turning out equipment because of a false alarm. 

Throughout Australia we found big, beautiful theaters in the subur- 
ban areas, so designed that in the rear of the orchestra on one side 
there is a double-glass partition which gives clear vision to the screen 
and a door which opens from the lobby into a room approximately 15 
to 20 feet wide by about 8 feet deep. They call this room their " Cry- 
ing Room" and they keep it exclusively for mothers who are forced to 
bring their infants and children to the theater. The room has its 
own amplifier horn and the mothers are able to see the picture through 
the double- vision glass, and njurse their babies. Should a child cry, 
the rest of the people in the theater will not be disturbed. 

In the theaters that have no "Crying Rooms," they render the 
following service in order to attract the mothers to the theater: A 
patron comes in with a baby in a carriage she buys her ticket (and ' 
generally speaking all seats are reserved) . She gives the usherette the 
baby's bottle and tells her what tune the child should get it; the 
usherette takes her ticket, fills out a slip which gives the woman' sname, 
location of her seat, hour of feeding, and pins it on the child. At the 
proper time, the usherette heats the bottle, goes to the seat, gets the 
mother and the mother comes out and gives the child the bottle re- 
turns to her seat and the usherette takes care of the child. This was 
really very amusing because we thought we had enough to do to 
operate theaters and take care of our public, without arriving at the 
stage where we also had to act as nursemaids! However, you would 
be surprised at the way this service is received and appreciated. 

On the opposite side of the rear of the theater they have a similar 
room with about 12 seats which they set aside for private parties. 
People having a dinner party at home, and wanting to make a film 
show part of the evening's entertainment, can reserve this entire room 
for the performance. In this way they have the pleasure of having 
their own crowd together separate and apart from the rest of the 
audience. Should they have had a little too much to drink, they, in no 
way, either by conversation or actions, disturb the rest of the people in 
the theater. This is a popular custom that might well be incorporated 
in our plans throughout this country. The only addition that might 


be added would be to create a private lavatory within the confines of 
this room. 

Generally throughout Australia you will find that many theaters 
are entered on the mezzanine, or as they call it, the- dress-circle floor. 
To get to the stalls (which is the orchestra in our language) you must 
go down a flight of stairs. To get to the balcony you must walk up a 
flight of stairs. From this you will see they try to prevent the people 
using the better-class and more-expensive seats from having to climb 

Most performances throughout Australia have reserved seats. 
They run three shows a day matinee, 3: 30,- next show at 6:30, and 
the last show at 9 o'clock. -Most theaters have usherettes. The girls 
are attractive and very well gowned. Their dresses, shoes, and stock- 
ings are supplied by the management and are in exceptionally good 

In short, and apart from the fact that they have usherettes instead 
of ushers, it is very difficult to be in many of the typical Australian 
houses and not believe that one is actually in Chicago, Kansas City, 
Toledo, or Atlanta. The spirit and operation of the American motion 
picture theater has reached there more completely than it has any 
other place in the world. 

All the major American companies who have built and are operating 
theaters throughout the world have constructed them in the same 
style and manner in which I have just described. Wherever you go, 
any place in the world, you can generally tell from its operation 
whether the theater is run by American companies or by local interests. 

In constructing a theater in Cairo, there is the additional problem 
that one cannot excavate deeply; generally speaking, 3 feet below the 
curb is the* water line. Most buildings are constructed on wood or 
concrete piles, depending upon the type of building that is erected, 
and usually you have to walk upstairs to approach the lobby in order 
to create a basement floor. Reinforced concrete is used throughout, 
with the exception of the roof where, in some cases, large wooden 
trusses are used and in other cases, steel trusses. The fire regulations 
for exit purposes are similar to those in the United States. In Egypt, 
as elsewhere throughout the world, they look to our regulations as an 
example of the best methods of safety for their business.. 

Paramount is now building a theater which is very near completion 
in Lima, Peru. This house, when completed, will be the finest theater 
in all of Latin America. The structure is of reinforced Concrete, 

348 CRYSTAL April 

aluminum sheet roofing supported by steel trusses; the walls in 
general are plastered but in some cases have acoustical rock-wool 
blankets covered with perforated transite. This, of course, is only out 
in the front facia of the balcony and around the rear-wall portion of the 
theater. The theater lighting system is especially designed with the 
new Frank Adam Electric Company dimmer. The main ceiling has a 
series of high-hat recessed electric fixtures so that all light shines 
directly down on the audience. The interior also has a series of 
neon lighting running around the auditorium at the mezzanine floor 
level. The theater is designed in such a manner that the smallest 
amount of floor space is Used in the auditorium floor, mezzanine, and 
balcony. The theater is equipped with the American Seating Com- 
pany body-form chairs, fully upholstered throughout. 

It is customary in Peru that balcony patrons must enter the 
theater from a different entrance than those who patronize the 
auditorium and mezzanine floor. These people generally have been 
considered lower class and throughout Peru the balconies are equipped 
with wooden benches, concrete steppings, or wooden chairs. In other 
words, the poorer class of people are given no consideration whatso- 
ever, so far as conveniences and comfort are concerned. However, 
we feel that low-price patrons shall be considered just as important as 
the* others, and we have equipped the balcony with fully upholstered 
seats, given the balcony a lounge, nicely furnished, carpeted the floor 
and aisles, to the balcony, and given them beautifully tiled, modern 
rest rooms. 

Major American companies all feel the same way and we are striving 
to bring to the people of the world the better things in life which we 
have all been fortunate enough to give to all classes of people in 

In America we are not allowed to have class distinction, but hi 
many places throughout the world, and especially in Latin America, 
there is class distinction and the local theater owners and operators 
look down upon the low-admission people. American companies feel 
that they are the backbone of our business and that success can only 
come to us through continuous patronage of the theater by the 
middle and lower classes, and that a theater built to attract only the 
better*classes can never be a successful venture. 

On the exterior of the Luna theater there are a stainless-steel elec- 
tric sign and marquee signs with flasher borders, equipped with 
Adler lexers, using both neon and fluorescent lighting. The soffit of 


the marquee is equipped with gold and white glass mosaic and some 
of the predominating free-sfanding reinforced concrete columns are 
also covered with the glass mosaic. The entrance doors are herculite 
glass, new for the Latin American field. 

Much of the foregoing has had to do with improvements, innova- 
tions, new conditions, and new comforts which the American motion 
picture industry is bringing to many parts of the world. 


The rest of the world looks to us for the latest innovations in theater 
construction and equipment and they try to follow in our footsteps. 
One deplorable factor is, however, that in their efforts and endeavors 
to be as American as possible, they are making use of outmoded 
American plans and device s and are heedlessly following them instead 
of checking to make sure that what they are doing represents the 
newest in development. We hope, in time, and with all of the co- 
operation at our command, to remedy this situation at the earliest 
practicable moment. 

Theater Engineering Conference 

Physical Construction 

Note: For the Theater Engineering Session on Regular, Prefabricated, 
and Drive-In Theaters, Chairman Satz requested that all discussion be 
held until after the delivery of the last paper in this group. The material 
which follows, therefore, is in the nature of a panel discussion and deals 
with all four papers in this particular section. 


MR. S. CHARLES LEE : Is it better to enter a drive-in theater from the stage or 
from the rear? In one of your plans it appears that at least part of the time you 
enter from the rear of, shall we call it, the auditorium. 

MR. S. HERBERT Taylor: The answer to that question depends upon local 
conditions. The important thing is to provide a considerable length of driveway 
before you reach the ticket booth, so that cars are not backed up on the highway. 
In some cases, if your screen were at the rear of the tract, you might possibly enter 
in the front of the theater, but where your screen is on the road side of the tract, 
which usually is the case, we are extending the entrance drive back in some cases 
to the rear ramp and in some cases about two thirds back in the theater. 

MR. LEE: In other words, it has no effect on the operation, or from the stand- 
point of the lights of the car approaching the drive-in theater, whether you enter 
from the screen side or whether you enter from the rear. 

MR. TAYLOR: The lights have been screened out when the car is making its 
turn into the theater tract. After that you can instruct drivers to turn out their 
lights. Very often natural conditions accomplish the screening. 

CHAIRMAN LEONARD SATZ: I should like to ask Mr. McNamara if he considers 
the 23-inch seat a little too wide? By providing a seat of extra width, would it 
permit the patron to shift around in the seat too easily from side to side and 
thereby cause discomfort to the persons sitting directly behind? Is there any 
limitation that you would set on the width of the theater chair? 

MR. JOHN J. MCNAMARA: In my opinion 23 inches is not too wide, but any- 
thing beyond 24 might prove so wide that the people would slouch sideways rather 
than sit straight. 

MR. BEN SCHLANGER: The 23-inch chair is too wide. It is advisable not to 
have a chair any wider than necessary, because it will permit the person in that 
chair to shift. What the person needs is not a 23-inch chair, but he needs elbow 
room, and, if possible, extra arm blocks for each person should be provided. In 
other words, I can visualize space in between seats. Even a very stout person can 
sit very comfortably in a 21- , or 22-inch chair, providing that he has enough elbow 

MR. MCNAMARA: My assumption was that it would be from center to center 
of seats, rather than having the seat itself 24 inches, so that 24 inches would take 
in the arm block. 

CHAIRMAN SATZ: Then I think there has been a misunderstanding. Mr. 
Schlanger, we are very much interested in double-arm blocks. In fact, before 



we placed orders for a large amount of seating recently, we inquired as to whether 
or not that would be practical. It did not work out, principally because of 
the high loss of seats that would result. 

MR. H. E. GREENSPOON: Mr. Lee made a statement that he hoped to build 
theaters for about $75.00 a seat. Could Mr. Lee elucidate and give us a little 
more detailed information about how that is possible? We are financing our- 
selves up in Canada, building theaters for about $200.00 to $225.00 a seat, and 
this information would be very welcome. 

MR. LEE: It is possible to build a theater for $75.00 a seat as at the present time 
I am doing it. The form of construction will only apply to areas in which the 
ordinance follows approximately the Uniform Code. I think the Uniform Code is 
now accepted in some 500 cities in the United States. So I shall confine myself to 

The main form of construction that we have used is, starting with a flat slab, we 
built below ground with reinforced concrete and brought our walls up to six inches 
above grade. From this point on we are using what is known as the Lamella truss 
system without any reinforcing rods across the span. The truss system is adapt- 
able; if you use a 50-foot span you can use 2-inch lumber, and by fireproofing it, 
we have found that we are well within the limits of the Code. 

We have used plaster to the extent of nine feet above the grade, and over this 
we are applying a sheathing, first a good sheathing and over that an interlocked 
aluminum sheet. This gives us complete waterproofing, and a very low-cost 

At the front of the theater, we designed a tower, and by b,uilding this tower of 
staggered pipes, we have been able to secure a very interesting effect. We have 
buried into the slab some floodlights, and by having changeable colors, I think we 
are going to get some showmanship out of it. 

On the front, we have used a combination of stone and plaster and the major 
portion above the marquee line will be of ribbed glass running in two different di- 

The present indication is that the theater will be very interesting in appearance, 
and at the present time I have costs in which I can award a general contract at 
$75.00 per seat. 

CHAIRMAN SATZ: Would you mind explaining that aluminum interlocked con- 
struction. Does that carry right up and around the roof? Is the roof of curved 

MR. LEE : Completely around, yes. 

CHAIRMAN SATZ: Similar to the radius of a Quonset hut? 

MR. LEE: We have a slide here that shows one adaptation of it on a 2500-seat 

CHAIRMAN SATZ: And the interior finish? 

MR. LEE: For the interior finish we are using expanded metal with an 
insulating material underneath the expanded metal. By painting the expanded 
metal we are going to obtain an architectural effect with our colors, and by having 
the insulating material, such as rock wool, behind the metal screen we shall take 
care of our acoustical correction. At the present time we are experimenting with 
Palco bark for that purpose, which on the West Coast is a little cheaper. 


CHAIRMAN SATZ: Is that the only acoustical treatment you are giving the 

MR. LEE: No, the rear wall is a perforated masonite with rock wool. 

MR. SCHLANGER: I should like to refer again to seating, because I think it is too 
important to ignore. You made a statement, Mr. Chairman, that the double- 
arm-block system used up too much space. I am not for or against double-arm 
blocks at the moment, but I do want to explain some dimensions. For example, 
if we had a 20-inch chair that had a double-arm block system, that is, on each side 
of the chair, it would be 20 plus I 1 / \ inches on each side. That would be 23 inches. 
So that if you were willing to devote 23 inches to a chair, which is not unusual, 
then youi arm blocks would not be taking up too much space. It is purely a mat- 
ter of simple arithmetic. 

You do not use double-arm blocks hi all the seats, but in staggered-seating plans 
where you use this system to help control the position of each viewer, so that he 
has a clear view between the heads in front. It may very well be that when the 
exhibitor becomes accustomed to more space per patron, as he has in back-to-back 
dimensions, that 23 inches devoted to each person will not be considered very 
much in the near future. 

CHAIRMAN SATZ: By a double-arm block, do you mean one solid piece of extra 
width or two separate blocks on separate standards? 

MR. SCHLANGER: At the present time that is just two separate arm blocks made 
up of two separate chairs. Many seating companies seem to be investigating the 
possibility of combination arm blocks of a wider width. 

CHAIRMAN SATZ: With double standard throughout the row? 

MR. SCHLANGER: I do not know what they are going to do. It may be a regu- 
lar standard, it may be a double standard. They are investigating that now, but 
have come to no decision. 

CHAIRMAN SATZ: Mr. Alexa, would you care to say something about that? 

MR. F. W. ALEXA: At the present time the standard chairs are from 18 to 22 
inches, but the 18-inch chair is no longer used. The widest chair at the moment 
is 22 inches. Above 22 inches you run the cost of the chair up pretty high, be- 
cause of the difficulty of preparing dies to form the steel backs. The average 
chair width normally used is about 21 inches. We have installed some chairs here 
recently that had an arm block that was about 4 inches wide, and the purpose of 
it was that it could be used for writing as well. This happened to be in a lecture 
room, and it did not have a bad effect at all. We used a chair about 21 inches wide 
with this wide arm block, and it did not take away from the comfort of the chair. 
There should not be too much objection to the idea of breaking up the chairs in 
sections and using double-arm blocks. The only cost involved there is an extra 
standard, and if that is going to achieve what you are after, good sight line and 
comfortable position, there should not be any objection. 

MR. FREDERICK J. KOLB, JR. : In your drive-in theaters, Mr. Taylor, what 
level of screen illumination and what level of surrounding illumination are you 
seeking, particularly for a 60- or 72-foot screen? You said in one installation you 
provided some artificial moonlight which, I take it, provided a constant, perhaps 
fairly high level of scattered light, and I wonder what you are planning to reach in 
that level, and then what you do for screen brightness to provide a satisfactory 

1948 DISCUSSION 353 

MR. TAYLOR: I regret I am not prepared to give you an answer on that sub- 
ject. The situation is this: Soft moonlight, we know by experience, does not in- 
terfere with the illumination on the screen. The illumination on a large screen is 
not up to indoor standards, we know that also. But we make up in size for lack 
of illumination. 

It is remarkable how well you can see. If you care to drive just ten miles from 
New York City, you can go over to Paramus, New Jersey and see the size screen 
you were talking about. You can stand on the other side of the fence, some 700 
feet from the screen, and see the picture fairly well. 

CHAIRMAN SATZ: Mr. Kolb, do you have- any ideas of your own as to what the 
level of screen illumination of that motion picture should be? 

MR. KOLB : Well, I have some ideas, but I do not think anyone can reach them. 

MR. LEE: May I ask Mr. Taylor what he considers the farthest row in which 
the occupants of the average car can see without complaints? 

MR. TAYLOR: We are planning a theater now with a 15th row. A car in the 
rear ramp will be about 660 to 670 feet from the screen. That theater will have 
the largest size screen, of course. The capacity of that theater is over 1000 cars. 

MR. LEE : That answers my question, although I have never been able to see 
clearly p"ast the 7th row, myself. 

MR. NEILL WADE: Mr. Taylor, could you say something about the surface 
treatment? Is there anything special needed on these outside screens? 

MR. TAYLOR: The surface treatment of the tract itself, the ramps, or the 
screen itself? 

MR. WADE: The screen on which it is projected. 

MR. TAYLOR: No, they require very little special treatment, because the screen 
is so large that any slight irregularities are compensated for, by the size of the pic- 
ture. We were somewhat afraid of that when we put steel plates on the face of the 
screen, because there is a slight rippling effect in the steel plate, but in actual prac- 
tice it worked out very satisfactorily. The plates are simply painted white. 

MR. WADE: The number of units that make up the screen brought that ques- 
tion to mind. Mr. Schlanger was talking about seats. With the advent of these ( 
new plastic materials, would they be suitable and wear longer than some o/ the ' 
fabric covers which are being used as an upholstery? 

MR. SCHLA'NGER: I do not have any wear tests on those. If you mean the 
plastic-coated fabrics, some of the good ones stand up pretty nicely, and they are 
more sanitary than the fabrics. The fabrics are a little better from an acoustics 
standpoint. The fabrics are not so good from the cleanliness standpoint. There 
are many factors that enter into it. However, there is a large variation in wearing 
quality of these plastic-coated fabrics. Some of them are excellent. 

CHAIRMAN SATZ: Mr. Wade, I might mention that during the Maintenance 
Session, I think there will be persons here who will be exceptionally well qualified 
to speak to you on the subject of vinylite resins or any of the other plastic-type 
coverings as compared to the old-style leatherette. 

MR. J. S. CIFRE: Mr. Taylor, have you given any consideration to the inclined 
screen, that is, inclining the screen so that it reflects the light back to the eye of the 

MR. TAYLOR: Yes, we have such a screen under construction at the present 
tune. It is not actually built as yet, but it is just about to be built. 


MR. CIFRE: What do you expect for advantage in that type of construction? 

MR. TAYLOR: You obtain a better throwback of light to the viewing area. 
Some of the light which is cast on a vertical screen is scattered upward, and that 
light is more or less lost so far as return to the theater patrons is concerned. We 
figure that with a slanted design we shall return more light directly to the cars that 
are parked in the theater. 

MR. JOSEPH J. ZARO: Mr. Lee, I believe you said that you awarded a contract 
at $75.00 a seat. Do you mean merely for your general contractor or for your 
entirely equipped theater? 

MR. LEE: That is for the construction without any equipment, but includes 
heating and ventilating, electrical wiring, painting, and all construction items, 
ready to move in the equipment. 

MR. ZARO: It is actually not a complete theater, then, at $75.00 a seat. 

MR. LEE : Unfortunately the parlance that the architect uses is usually for the 
construction of the building and the operator installs his own equipment. 

MR. ZARO: What are your costs actually running? 

MR. LEE: The equipment, as you know, could vary according to the type of 
equipment you selected and the seats. There are some persons who could tell you 
exactly how much your equipment will cost in a given size theater. For a 1000- 
seat theater, I would say that your equipment costs today run about $38,000. 

MR. ZARO: On your low-cost theater, what type of construction would you 
compare that to under prewar conditions? In other words, taking your theater as 
an over-all building, exterior and interior, how would that compare as far as 

MR. LEE : I should say that prewar that similar type of construction could have 
been built for nearer $40.00 a seat. 

MR. ZARO: Has any consideration been given on the West Coast to use of ver- 
miculite construction in wall-panel construction for theaters? 

MR. LEE: Yes, we have had vermiculite construction on the West Coast 
several times and have had it under consideration. We have a very great prob- 
t lem in connection with seismic loads, what you might term earthquake resistance, 
and we investigated vermiculite concrete from the standpoint of lessening those 
loads and also considered the crushing strengths that we could get out of it. We 
have never been able to use it with any degree of economy. 

MR. R. T. VAN NIMAN: Mr. Taylor, what experience have these theaters had 
with the theft of car speakers, with damage from the weather, and with damage 
suits from patrons who drive off without taking the speakers off the car windows? 
. MR. TAYLOR: There has been very little loss of speakers. Of course, some 
occasionally are lost but not many. 

So far as maintenance is concerned, the products that our company has handled 
have stood up v.ery well. I know of no such instance where patrons have had dam- 
age done to their cars by driving off without taking the speakers off the windows 
and have sued the theaters. 

CHAIRMAN SATZ : I should like to ask Mr. Taylor if there are any figures that he 
could use to explain his statement that family business predominates. Can you 
give us an average of how many people appear in each automobile, or is there any 
guess that you would care to give as to what percentage of your business is family 

1948 DISCUSSION 355 

MR. TAYLOR: The average per car runs around three, and I would say that 
the family business is 75 to 80 per cent of the theater business. 

MR. WADE: Mr. Taylor, could you give us any idea of how the cost per patron 
for the construction of drive-in compares with the figures we have already heard 
for the indoor theaters? 

CHAIRMAN SATZ: Would not that have to be cost per car? 

MR. WADE: Let us reduce it to a common denominator. What is the patron 

MR. TAY.LOR: A fully equipped drive-in theater, from 660 cars to, say, 850, will 
vary in cost from $100,000 to $200,000. If you take the number of cars and 
multiply them by three, you can pretty nearly produce a patron figure. 

Of course, it is possible to construct drive-in theaters for less than that. But in 
the Metropolitan New Jersey section, they are going in for first-class construction 
right now. 

CHAIRMAN SATZ: Do you base that on any particular average for wages or any 
standard in this area? 

MR. TAYLOR: No, that is New Jersey experience. It is North Jersey, where 
you have a very high wage level. 

MR. VAN NIMAN: I should like to ask Mr. Taylor whether there is any prospect, 
with the advent of high efficiency for the focal lens, that it would be desirable to 
move the projection room closer to the screen, so that not so much space will be 
lost in front of the booth because of the light beam. As it is now, it is about 200 
feet for the average distance. 

MR. TAYLOR: The usual distance at present is 239 feet. Perhaps Mr. Smith 
can answer your question. 

MR. V. C. SMITH: I do not know whether I can answer that question or not. 
Recently, I was with Bausch and Lomb, talking over this particular problem, and 
apparently it is quite difficult to solve. I think it will be a few years before this 
becomes a possibility. It would be desirable for one or two reasons, in that you 
would be able to park cars in the space that you are now using for the projection 
booth, and you would also be able to cut down the amount of space between the 
projection equipment and the screen. 

MR. VAN NIMAN: Who is going to make the lenses? 

CHAIRMAN' SATZ: You will just have to wait on that. 

MR. ALBERT STETSON: I would like to have Mr. Taylor give us an expression 
regarding the advantages and disadvantages of wooden-screen structures compared 
with steel. I am thinking of safety as well as expense. 

MR. TAYLOR: My vote goes for the steel. The screen structures are getting 
so large that I do not see how you can secure safe and economical construction 
with wood. It may be possible, but I prefer steel. 

MR. LEE: Mr. Taylor, do you have any information where the run of the pic- 
ture in the drive-in theater has paralleled the neighborhood run? What impact 
has the drive-in theater on the indoor-theater attendance? 

MR. TAYLOR: That is a question I am not competent to answer. 

CHAIRMAN SATZ: We shall try to get an answer for you, Mr. Lee, before you 

MR. JAMES FRANK, JR: Mr. Taylor, what is the amount of land required for 
various sized theaters, the number of acres for 500- to 700-car theaters? 


MB. TAYLOR: I can, in a general way. The actual area of a 660-car theater is 
about eight acres; actually, eight and a half. This is just the bare ground for the 
theater. If you want to protect yourself from side encroachments, if you want 
ground for some other purposes that might develop in connection with your 
theater, you certainly want to provide more. As a general rule, you cannot buy 
just the acreage you need because the theater is more or less pie-shaped. So with 
the 660-car theater, I should say you would need from 12 to 15 acres; for an 850- 
to a 1000-car theater, you need from 15 to 20 acres. 

Many times when you go to buy a site you will find that you can obtain the 
balance of the tract, which might be quite sizable for very little more than what is 
desired, and the choice part of it will cost you a lot more per acre than the balance 
of it will. So the tendency has been to take tracts that are larger than needed, 
which gives some reserve for future business which might develop in connection 
with the theater. 

MR. SCHLANGER: Let us go indoors for .a while. One of the things that I 
think would be helpful would be for the architects to collaborate on some stand- 
ard on sight lines. Mr. McNamara, in figuring the clearance of sight lines in a 
theater, did you follow the principle of getting the clearance over the heads of the 
persons seated immediately in front or over the heads of people seated two rows in 
front of a spectator, or any other method? Soon this will become an item that 
will be settled by the Society but I think now is the time to get started. 

MR. MCNAMARA: I think that it would be impracticable in most cases to ob- 
tain the sight line directly over the head of the row directly in front except in the 
forward rows of seats. More important would be the staggering and the sweep, 
rather than trying to see over the head of the row directly in front, which would be 
almost impossible in most cases. 

MR, SCHLANGER: Do you calculate sight lines to clear the head two rows ahead? 

MR. MCNAMARA: Not exactly, it would be more the second row with the stag- 
gering of the seats, which would give you a good sight line. 

MR. SCHLANGER: I do not understand the answer very clearly yet. My 
question was, if in making your calculations, you make your calculation over the 
heads immediately in front, which you say you do not, and you would rather use 
staggered seating, as I gather, Instead of trying to get over the heads in front, be- 
cause that would be giving you too steep a slope. So then we have to figure that 
sight line over some head or some in-between compromise. So the question then 
is, do you figure the clearance ahead over two rows ahead? 

MR. MCNAMARA: No. I do not figure it at all over the row ahead. I figure 
the sight line on an arithmetical progression, allowing sufficient space to give good 
sight lines, or with slight staggering, and leaving the front portion of the theater 
more or less flat. 

MR. SCHLANGER: It still is not clear. I assume, then, you are looking between 
the two heads hi front of you, that the heads in the front of you are not in the way, 
is that correct, the two heads in the next row in front of you are not in the way? 
You do achieve that? 

MR. MCNAMARA: That is correct. 

MR. SCHLANGER: Then, beyond that, must not the person see clearly over the 
head in front of that? 

1948 DISCUSSION 357 

MR. MCNAMARA: Of course. 

MR. SCHLANGER: Do you figure your sight lines over the heads two rows 

MR. MCNAMARA: But I do not figure each row for the second row ahead or for 
the first row ahead. I do not think anybody does. You do not figure theater slop- 
ing on the basis of seeing over each row and figuring each second row, but use this 
theory as a method of checking the sight line. 

MR. SCHLANGER: If we have the two heads in front of us out of the way, they 
are no longer a problem, so that the row immediately in front is no problem. 
Then the next problem is to be sure that you see over the head in front of that for 
the next row, and if you do see over the head two rows ahead, you are going to see 
over all the other rows. I have noted in the past, in checking up floor slopes in the 
history of theater design, that some compromise was made whereby they did not 
figure over the head immediately in front, and neither did they figure immediately 
over the head two rows in fro'nt. There was sort of a safety margin. They 
figured somewhere in between, which is a waste in theater floor slope. So I am 
just wondering what practice you or other architects* follow. 

MR. MCNAMARA: My practice is not to figure each row or each second row. 
We figure the entire house. The sight line is also determined by the location of the 
screen. So that the question of figuring just over the head of the person directly 
hi front is not, in my estimation, a practical way to figure the entire sight lines for a 

MR. SCHLANGER: It is impossible to figure a set of sight lines without having a 
set of assumptions. You have to start with an eye and it has to see over some- 
thing. You have to figure clearance over some head. 

MR. MCNAMARA Maybe that is the way you figure it, Mr. Schlanger, but it is 
not the way I figure it. 

MR. SCHLANGER: The other is a mystery. I should like to get it out in the 

CHAIRMAN SATZ : May I suggest we get the opinion of a third architect. Would 
Mr. Lee care to tell us how he figures that? 

MR. LEE: I think everyone here who is interested in sight lines would like to 
see these two series projected on a blackboard, or on a screen. There are two 
schools of thought here. Mr. Schlanger has one, which of course we highly regard, 
and Mr. McNamara has another, which is equally well regarded by the other 
school of thought. I think that it would be very interesting if they would present 
their views on the blackboard and give us a chance to then judge whether or not 
there are errors. (NOTE: The blackboard demonstration was not held because 
of time limitations. The Editor.) 

MR. SCHLANGER: These are not two theories. This is just simple arithmetic, 
the theory comes later. I really would like to use a piece of chalk and a black- 
board and illustrate what has been said in order to follow the problem through 

CHAIRMAN SATZ: Maybe we shall be able to do that. In the meantime, could 
I dispense for a minute with the services of the engineers and ask a practical man 
to give us his opinion? He has made many installations and I am sure he knows a 
lot about the subject. Mr. Alexa, would you care to get into this controversy? 

MR. ALEXA: In a way it rather crimps my talk tonight which is based on sight 


lines. There is no doubt that the ideal condition is that the sight line should clear 
the head of the row directly in front, and as Mr. McNamara and I believe Mr. 
Schlanger agrees, it is impossible to do that because of the restrictions due to the 
codes that govern the slopes of floors. So the next approach to this would be to 
see between the heads of the people directly in front of you, and in that case all 
you have to do is to make sure your sight line clears your second row ahead of you 
regardless of where the patron may be sitting in relation to the direct line of view. 
In order to prevent the situation that presents itself where your chairs are directly 
behind each other, you would have to stagger the chairs and, as Mr. Schlanger 
says, it is a matter of mathematics that could be easily demonstrated on a black- 

MR. SCHLANGER: Mr. McNamara said that the use of as flat projection angle 
as possible is desirable. What do you think, Mr. McNamara, is a maximum angle 
that you would adhere to, that is, not go over a certain angle? 

MR. MCNAMARA: About 20 degrees. 

MR. SCHLANGER: The recent American Standards Association report mentions 
this as 12 degrees. The SMPE used to use 18 degrees. That is a pretty important 
angle. The distortion caused by 20 degrees is serious. 

MR. MCNAMARA: I said that would be the maximum. 

MR. SCHLANGER: I believe the American Standards Association comes closer 
to what it ought to be, and that is 12 degrees. In a theater we designed in Lima, 
Peru, which Mr. Crystal explained, we had a double-balcony theater, and the de- 
gree of projection is somewhat less than 13 degrees. 

CHAIRMAN SATZ: I should like to ask Mr. Lee to explain, or to amplify, his 
statement made before about dimming out neon. We recently had occasion to 
use cold-cathode illumination and we had quite a problem before we got the re- 
quired intensity, that is, for running lights, and if you would like to amplify your 
statement, what you mean by dimmed-out neon, I should be very much 

MR. LEE: We have used dimmers on neon circuits for quite a number of years. 
My electrical engineer would have to go into the technicalities of the exact wiring 
diagram, but we use Autrostat dimmers, and with the Autrostat dimmer we have 
had no trouble whatsoever in dimming everything, except red. 

CHAIRMAN SATZ: We used cold-cathode, and as we dimmed cold-cathode the 
color characteristics would change. 

MR. LEE: I have corrected the color characteristic. In fact, recently we have 
used an entirely different theory. We have used white neon, and, by a very 
simple process of painting, have obtained the desired color. That left us with no 
problem at all. We started by using gelatine and then we abandoned the gelatine 
>,nd painted a strip on the white neon. By simple experiment,' it probably takes 
us half a day, depending on the colors we have used in the auditorium, to get the 
exact tone that we want on our neon, and it has eliminated a great deal of trouble. 

CHAIRMAN SATZ : Have you used cold-cathode to any extent in any of your in- 

MR. LEE : We have cold-cathode, but not with the dimmer systems. We have 
always used neon. 

CHAIRMAN SATZ: How large a transformer do you generally use for running 
lights, not house illumination? 

1948 DISCUSSION 359 

MB. LEE: I do not think I can answer that. 

CHAIRMAN SATZ: We found that 120- and 60-miUiampere transformers in 
some circumstances were still too much. We had to use 30-milliampere. 

MB. LEE: On our neon we have used 30's almost consistently; on the cold- 
cathode, I cannot say, we have used so little of it. 

CHAIRMAN SATZ: We have also had good results where blue lights were indi- 
cated using colored tubes and the old-fashioned neon to get a low, dim intensity. 

MB. LEE: You can do it with a paint that saves much time and money. In 
that connection, by using the white neon and painting the strips on it, you can 
change it, for instance, with the seasons. We have changed some houses entirely 
when we have gone from the cold season to the hot season. We have just wiped 
off the paint and changed the whole character of the auditorium. 

CHAIBMAN SATZ: Is there any noticeable blistering or peeling of the paint 
which causes spotty illumination? 

MB. LEE: Not at alii 

CHAIBMAN SATZ: Would you consider that a practical thing to do? 

MB. LEE : Absolutely. I can prove it by many years of use. 

CHAIRMAN SATZ: Then I understand that you are in accord with atmospheric 
lighting in so far as summer and winter seasons are concerned. 

MR. LEE : The operators have different opinions on that, but I think that there 
are quite a few of them in different territories that have taken the position if they 
can change the character of their houses from time to time, it adds interest. 

Theater Engineering Conference 

Auditorium Design 

Seating Arrangements, Sight Lines, 
and Seating Design* 



Summary This discussion will not be an attempt to consider, from a 
technical point of view, the problems of theater design as the author is neither 
an architect nor an engineer. Rather, it will be an attempt ito call attention 
to some of the problems and advancements regarding the seating layout and 
the design of seating areas for visibility as they have been observed during 
twenty-three years' association with the American Seating Company as a 

IN THE PAST, the only part played by the seating company was the 
preparation of the seating plan to show the quantity and sizes of 
the chairs. Then, as motion pictures became more popular, the need 
for comfort and better visibility. became evident, and architects and 
guilders looked to the seating companies for better design and comfort 
of the seating equipment. 

Reluctantly, the ' 'legitimate theater" accepted the motion picture. 
With the growth of motion pictures it became apparent that the fac- 
tors of design for these two separate fields of entertainment had to be 
approached differently. The "legitimate" had to be designed for 
clear visibility of the stage, a horizontal field of vision, while for motion 
pictures the field of vision is the vertical plane of the screen. Because 
of the functional difference of the legitimate theater and the motion 
picture theater, the combination of these two functions proved to be 
costly and unsatisfactory, with the result that a new approach to the 
design of the functional form of the motion picture theater had to be 

Important factors in theater design are clear and unobstructed 

* Presented October 20, 1948, at the SMPE Convention in New York. 


sight lines to the screen, the vertical position of the screen being one 
of the controlling factors. In the past, the screen position was in- 
fluenced by the stage level, and the physical conditions of the theater, 
such as the projection of the balcony over the orchestra floor, the 
height of the proscenium, and the projection angles. In other words, 
the location of the screen was a compromise to give the occupants of 
the orchestra floor and balcony the best possible vision under the 
existing conditions. Naturally, since the design was basically for a 
stage view someone had to suffer as vision to the top of the screen was 
obstructed for those seated under the balconies because of the balcony 
overhang. This screen location on the stage somehow became a fixed 
rule and notwithstanding the fact that the function was different 
many motion picture theaters came to be built still holding on to the 
traditional stage of the "legitimate" along with the rule of thumb that 
the screen should be located 12 to 24 inches above the stage. 

It was in the early thirties that Ben Schlanger presented, at one of 
your conventions, his studies of floor-slope factors for sight lines for 
motion picture theaters as distinguished from theaters designed ex- 
clusively, or at least primarily, for stage performances, and the re- 
verse slope then came into being. Like all new theories, at first it was 
belittled. However, this new method, like all new ideas, went 
through a series of improvements and steadily has been gaining recog- 
nition. This recognition is evident by the fact that our factory re- 
ports the need for manufacturing chair standards in a greater quantity 
for reverse incline than ever before, and this type of chair is now con- 
sidered standard equipment. 

Most of you will say you know all this but how does one go about 
designing a theater floor to obtain clear, unobstructed sight lines? 
First, there is no set rule that will give a standard floor slope for all 
theaters. Each theater must be studied and designed to meet the 
varying conditions of the site, capacity, and number of seating tiers 
desired, and the building code. 

The ideal sight line is one that will give unobstructed vision to the 
screen over the heads of occupants of the row directly ahead. This 
has been termed "first-row vision. ' ' This would result in a floor slope 
that would exceed maximum floor pitches as defined by most building 
codes and would present practical difficulties in construction. There- 
fore, it becomes necessary to take advantage of being able to see the 
width of the screen between the heads of the occupants of the row di- 
rectly ahead, with clear vision assured over the heads of all other rows, 

362 ALEXA April 

and requires the viewer to shift himself in the chair to one side or the 
other. This has been designated as "one-row obstruction," the row 
directly ahead being the obstructing row. To overcome this ob- 
jection, methods for staggering the chairs have been developed. The 
staggering of chairs requires careful study. Each chair must be taken 
into consideration as the visual angle changes with each chair position. 
When the chairs are properly staggered the result is the same as "one- 
row vision" and is the nearest approach to the ideal condition. In 
the side or wall banks of chairs the stagger is automatic for over 50 per 
cent of the chairs, while in the center bank very few seat positions are 
automatically staggered. 
The following methods for staggering the chairs are now in use: 

1. All chairs of the same size, with a half-chair stagger every other 
row; for example all odd rows having 14 chairs per row, all even rows 
13 chairs. This would mean the loss of one chair every other row, and 
would result in a half-chair aisle indent at each side. This method is 
only partially corrective. It is completely corrective when not more 
than 10 chairs per row are used. 

2. Varying chair widths for all rows with a varying aisle indent 
and sometimes no indent at all. This method is more corrective but 
requires special chair widths. 

3. By using three chair sizes in each row and alternating the order 
of the chair sizes every other row, for example, five 19-inch, four 20- 
inch, five 21-inch in all even rows; with five 21-inch, four 20-inch, 
five 19-inch in all odd rows. TChere would be no aisle indent as all 
aisle standards would be in alignment, nor would there be any loss of 
chairs. This also is only partially corrective. 

4. Varying chair widths for all rows and varying aisle indent* simi- 
lar to the second method described, except that the chair row or sec- 
tion would be broken up into two or more sections by the use of a 
double middle standard. In this way the varying chair width would 
be kept within the standard chair size eliminating the need of special 
sizes as would be required by the second scheme. This method is 
more corrective. 

There have been a considerable number of staggered seat instal- 
lations in recent years. As a matter of fact, at this time there are 
more installations coming in with staggered seating than previously. 
This is true especially in the case of reseating where it has been found 
that the introduction of staggered seating improves the sight lines 
while maintaining the existing floor slope. It may be well to note 


that not all building departments have approved the staggered plan 
which results in an indented or jagged aisle. However, ways and 
means are being considered to overcome this objection. 

The staggered-seating arrangement does not look so well on paper, 
nor when the empty theater is viewed from the stage. However, 
from the important point of view of the entrance end of the audi- 
torium, appearance does not suffer. The irregular pattern formed by 
the line of the chair backs gives the impression that the chairs were 
just thrown in, in comparison to the nonstaggered plan where all the 
chairs are in alignment. Since the main consideration, however, is to 
have the best possible sight lines for the greatest percentage of seats 
any objection as to appearance should be secondary. 

If the chairs do not fit the floor properly all careful calculations will 
have been of no avail. Since the chair standards for a downward and 
upward pitch are manufactured in increments of x /4 of an inch up to 2 
inches per foot for the downward pitch, with a recommended maxi- 
mum of iy 2 inches per foot and a recommended maximum of 3 /4 inch 
per foot for the upward slope, the best result can be achieved when the 
floor slope is designed to these inclines. This will result in a slightly 
greater total pitch in the floor than required but it will be on the safer 
side both in chair comfort and in viewing comfort. 

There are times when the design conditions call for an all-downward 
slope, while in other instances a floor slope, having an upward as well 
as downward slope, is desirable. In such a case, a careful study of the 
position of the screen must be made so that the downward viewing 
angles from the balcony, and the upward viewing angles from the 
main floor seats are balanced out to create the most comfortable 
angles of the greatest number of seats. In a vertical plane the ideal 
viewing angle is one that requires the least physical exertion to eye 
and neck muscles of the viewer. The ideal viewing angle would be 
zero degrees formed by a horizontal line from the viewer's eye to the 
center of the screen. 

The floor slope should be designed to place all of the rows as closely 
to this ideal angle as possible, taking into consideration, however, the 
contour of the site and other factors. The possibility of having seat- 
ing depths as much as 44 rows, because of the ability to see the en- 
larged screen from such a distance, has created the need for a depar- 
ture from the conventional downward slope. The all-downward 
slope, in such instances, would become excessive and would present 
difficulties in meeting grade conditions. Then again, the pitches of 

364 ALEXA April 

balcony floors become needlessly excessive when a completely down- 
ward floor slope is used. The ability to make floors generally flatter 
to meet these conditions has been made possible by the positive, care- 
ful seat staggering now developed and tested, and the flexibility in 
floor-slope treatment which takes advantage of the fact that the screen 
is a movable element in the vertical plane, the latter factor being the 
key point in differentiating between the necessarily fixed position of 
the stage in a legitimate theater and the optional position of the screen 
in a motion picture theater. 

It is no longer necessary to impress the theater public with over 
elaborate decoration or gilded gingerbread, but by keeping the design 
simple and by spending the time and money on the essential features 
of planning for the best sight lines and chair comfort, the departure 
from the old orthodox way will lead to better motion picture theaters 
and greater enjoyment from this type of entertainment. 


CHAIRMAN JOHN EBERSON : Our speaker has talked about the most important 
things in theaters, spacing and staggered seating. He has covered a very impor- 
tant item in modern theater construction out with gingerbread, in with the 
idea which makes a moving picture theater a place to relax and see a picture with 
the utmost comfort staggered seating will do it. 

MR. LEONARD SATZ : Would you mind repeating, Mr. Alexa, the second plan 
which you mentioned for staggered seating? 

MR. FELIX ALEXA: The second plan is to vary chair widths for all rows with a 
varying aisle indent and sometimes no indent at all. This method is more correc- 
tive, but it does require special chair widths. In this case you would have to 
use chair widths that would range anywhere from 19 to 26 inches in width. 

MR. SATZ: Do you not agree that the extra width as you mentioned, 26 inches, 
would allow the occupant to slide back and forth, and would not be in keeping 
with proper seating? 

MR. ALEXA: It has been found that this is not the perfect solution. There is 
a tendency for the occupants to move from side to side in their chairs. Further- 
more, it is costly to use special size chairs since most manufacturers have standard 
size equipment. They set up their equipment to certain widths and when you 
go beyond those standard widths, the maximum of which is 22 inches, it requires 
special handling. In most cases those chairs would have to be made by hand 
and would be very expensive. 

MR. SATZ: In the average installation which of the three methods, hi your ex- 
perience, have you found will give the least number of dead seats or obstructed 

MR. ALEXA: The fourth method would give the least number of obstructed 
seats. There would be some bad seats in front, but you could still work out the 
scheme with standard size chairs. 


MR. SATZ: Would you suggest that the indented row be illuminated for 
perfect aisle illumination? 

MR. ALEXA: In the case of an indented aisle, I would recommend that the 
aisle be illuminated as much as possible. It might be a good idea for every stand- 
ard to have a light on it so that people coming down the aisle could see these 
indented rows. The building departments in some cases claim that indented 
aisles form a hazard and that people walk into the projecting rows. If the aisle 
standards are equipped with aisle lights they no longer would be a hazard as the 
people coming down the aisles would be guided by the line of the lights. 

MR. SATZ: Do you think that illuminating the indented rows would outline 
the aisle seats sufficiently to prevent that? It is much more expensive to wire 
up every ro'w than it is every other row. 

MR. ALEXA: That could be the solution. There would at least be enough light 
to indicate the back of the chair in front of the indented row and, I think, that is 
what is desired. 

MR. BEN SCHLANGER : With the occasional double-arm-block system, the indent 
is minimized to such a point that it may amount only to about an inch or two in 
about 80 or 90 per cent of the cases. In some cases it will be about three or four 
inches. You are practically doing away with the indent if you take advantage of 
a double-arm block here and there. You are able to have center-to-center seating 
per person of almost any width you want, to make up the difference, so that the 
indent at the end can be eliminated. 

However, it is desirable to light up the aisle as much as possible. In that case 
every other row would be sufficient ; that is, every other row you diagonally skip 
across from one side of the aisle to the other. So, actually, you have light every 
row with an every-other-row lighting. 

MR. A. L. TREBOW: Do I understand that you advocate not having the double- 
arm block on every seat on the main floor in order to take advantage of the stag- 
gered seating? 

MR. SCHLANGER: It is not exactly advocating it. It is an expedient, the idea 
being comparatively new. The idea really is not new, that is, we are in the process 
of perfecting an idea which we see is good. Therefore, the manufacturers have 
not quite caught up with what they could do for us, although I know they are 
really working on the problem. As an expedient method, you could use a double- 
arm block only where needed. Eventually, I believe, instead of a double-arm 
block they may develop a single-arm block that is wide enough to take up the 

MR. TREBOW: What about the primary principle of having 80 per cent of the 
seating on stepping?. I refer entirely to the fact that there are seats on level 
platforms, and 80 per cent of the seats shall be on level platforms two or three 
inches above the row preceding it, and the aisles then take the slope. Why would 
not that take care of a good deal of your sight-line problem? 

MR. SCHLANGER: I think it was partly answered, but maybe not amplified 
enough in the paper that Mr. Alexa gave. We have found, I think, that there are 
a couple of hundred theaters erected, in which we have eliminated the need for 
such an excessive slope. Such a slope would cause the necessity for elevated plat- 
forms level platforms one above the other. 

A floor slope is a necessary evil. Theoretically, an absolutely flat floor is better 

366 ALEXA 

than a sloped floor if it would give you clear vision. There was a theater built in 
Paris in the early '30's on an absolutely flat floor. It is usable because the bottom 
of the picture happens to be about nine feet above the floor, and the seats are very 
carefully staggered. That is not a complete solution, but it is at least an indication 
that flat floors are very possible. When I say flat floor, I don't mean a true flat 
floor, but something that is almost a flat floor. 

Let us consider that theater in Paris and improve upon it. First, the screen is 
too high for the front rows. We shall cure that. The sight lines from the rear 
part of that theater may be not quite enough, because the floor is flat all the way 
back. We shall raise that floor up a little bit in the back, until we cure that. In 
the middle of that theater you will find that the sight lines are good. The objec- 
tion in the front is that the people are sitting too far below the screen. If you had 
a curve there that was coming down from the back, going flat, and then coming 
up a little bit in the front, it would cure all faults. 

MR. TREBOW : That is the theory of the upper reverse curve ; the reverse curve 
as you call it. 

MR. SCHLANGER: It was originally called a reverse curve, but it does not look 
like it. If you have seen some of these theaters, they look like flat floors. The 
layman walking in does not feel any particular slope because it is so flat. 

MR. TREBOW: Does that not require staggering just the same? 

MR. SCHLANGER: It certainly does. Staggering is an essential part of the 

MR. TREBOW: What if you have a city code that requires even aisles? 

MR. SCHLANGER: That is the thing that Mr. Alexa was discussing how you 
can get an even aisle with staggered seats with the occasional double-arm-block 

MR. TREBOW: Am I to understand you that it must resolve itself in an occa- 
sional double-arm-block system? 

MR. SCHLANGER: That is the best system I have found so far for evening out 
the aisle line. 

Theater Engineering Conference 

Auditorium Design 

Increasing the Effectiveness of 
Motion Picture Presentation* 



Summary Ideas are proposed for refinements in the presentation of mo- 
tion pictures. It is pointed out here that diamatic values can be heightened 
and visual comfort increased by different uses of a largei screen. 

GOOD SOUND and color are already, a definite part of the motion 
picture. The motion picture devotee now receives these mar- 
vels of science with an almost cold casualness. Motion picture en- 
gineers have developed a reputation that becomes a task to uphold. 
If you create the unusual, it is expected of you. The industry turns 
its head to science to help even out 'the business curve at the box 
office. In taking stock of the storehouse of ideas yet to be exploited, 
one must be impressed with the possibilities of the following thoughts. 

The motion picture theater auditorium and the screen can be given 
fresh thought if it is realized that the motion picture can be delivered 
with greater dramatic impact to group audiences than is now ex- 
perienced with present methods. This fresh thought can start with 
the basic idea that there could be a closer relationship between the 
film production problem and the problem of exhibiting the film. The 
cinematographer and film director can be aware of the fact that his 
work will be more effective if he considers the exhibition problem. 

It should no longer be considered that the potential effectiveness of 
a film is limited to all the endeavors that go into it until the time that 
it is put into the can and marked for delivery to a theater. This 
attitude may be suitable in considering tke phonographic record to 
be played in a juke box, but million-dollar picture productions de- 
serve a more studied presentation, environment, and cinematography 
keyed to group-audience reception. 

* Presented October 20, 1947, at the SMPE Convention in New York. 


368 SCHLANGER April 

A possible approach to this problem is based on a number of studies 
beginning with a paper by the author, 1 dealing with cinematographic 
technique followed by two other papers dealing with auditorium 
lighting 2 and screen-border synchronous lighting. 3 Reference is also 
made to a paper by Luckiesh and Moss 4 dealing with screen light 
and the lighting of its environs. All of these papers show that: 

1. Cinematography has to be reappraised in the light of its re- 
lationship to auditorium viewing conditions. 

2. There is a lack of transition between the projected picture and 
its environs, both from psychological and eye-comfort aspects. 

3. The auditorium appearance is not one that enhances the pro- 
jected image, and that it is a distracting element whereas it should 
function only as a neutral shelter. Cutter 6 also refers to this problem. 

The thoughts presented here are intended to show that these are 
phases of one problem, that is to heighten the dramatic values and 
provide the maximum in visual comfort as a necessary part of this en- 
deavor. The ideas proposed are for refinements in a known art, and 
since they are not revolutionary, no important changes in the highly 
developed mechanisms of taking and projecting pictures need be ad- 
vocated. Most important is the point that the 35-mm film is ade- 
quate for the improvements proposed and that projection lighting 
systems now developed are also adequate. Experience has now 
shown that pictures up to 30 feet in width can be projected success- 
fully, giving a satisfactory image. The recent increase in ^he number 
of drive-in theaters has furthered the development of projecting pic- 
tures even larger than this. The ideas here presented call for an in- 
crease in picture size of between 20 and 25 per cent. This amount 
of increase over present indoor picture sizes therefore comes well with- 
in the realm of practicability. If one thinks carefully about looking 
at the motion picture now, and especially from the rear half of the 
auditorium where some of the most important seating positions are, 
it will be realized that the picture looks like that smaller television 
screen at home even though physically the picture in the theater is 
so much larger than the television screen. The average architectural 
effect in the present theater auditorium and the size of the picture 
creates the appearance of that television screen in the home. Not 
only does the present screen have this disadvantage but it also, to a 
great degree, limits the cinematographer inasmuch as his central figure 
has to remain more or less in a fixed position even when it is supposed 




to be in motion. To create motion he has to resort to having the 
background move while the foreground point remains more or less 
fixed. Although he has been fairly successful in creating this 
illusion of movement, it is too constricting as will be shown later. 

A larger screen and a different use of a larger screen are here proposed. 
Many attempts to use a larger picture have failed in the past. It 
seems as though they have for several practical reasons. It will be 
remembered that one of the most effective results of the extra -large 
picture was when it was used only as a tonic to emphasize a pano- 
rama, the chorus line in a musical, or a special impact that was put 
across by the sheer scale of the image. This might indicate that the 
large screen, as it was used, was not necessary throughout an entire film 
presentation. The changing picture size in the old "magnascope" 
screen was managed by the use of irislike black masking and by chang- 
ing lenses. This arrangement called for extra costly equipment and 

still had the distinct disadvan- 
tage of a dark picture surround. 
Continuous use of the entire 
enlarged image" as with the 
"Grandeur Screen" throughout 
a film led to having too much 
happening on the screen, result- 
ing in a lack of dramatic con- 

The above shows the faults of 
both the enlarged and the pres- 
ent picture size. The purpose here calls for a large screen which is 
always revealed to the audience during performance time, but the 
screen would be used in an entirely new way. There will be no necessity 
for mechanical moving maskings as with the old magnascope idea. 

Fig. 1 is a view looking at the proposed screen. The area enclosed 
by line 1 represents the average present screen size, while 
line 2 shows the proposed enlarged screen area. The bean- 
shaped form enclosed by the dotted line indicating area A will be re- 
ferred to as the distinct visual field, while the area remaining 
between line-# boundary and the bean shape will be referred to as the 
peripheral vignette. Area C outside of boundary line 2 is the surface 
outside of the screen area. The bean-shaped area A is intended as a 
momentary shape only; this shape may change in form and size in 
accordance with dramatic requirements. Assume first that instead 


Fig. 1 

370 SCHLANGEE April 

of projecting a picture of approximately 18 feet wide from 35-mm 
film, that a picture approximately 5 feet wider and of a height that 
would be consistent with present standard proportions is projected. 
Right here there seems to be a handicap presented by the difficulty of 
enlarging the screen area because of proscenium-size limitations and 
balcony overhang cutoffs in existing theaters. The answer to this is 
that wherever these difficulties can be overcome economically with a 
change in structure, the effect proposed would be most desirable, but 
where such conditions cannot be avoided economically, the effect 
still will be better than the present one because any portion of the en- 
larged screen that would be cut off from view because of an overhang- 
ing balcony would not create any serious loss of picture area. Loss of 
view of some portion of the peripheral vignette would not prove 

Now what happens in Hollywood? Generally the picture would be 
taken on film as it is now. But, the director and cinematographer be- 
come aware of a new freedom in picture composition and in creating 
dramatic impact. His focal point of action can be concentrated at 
center, left, right, any of the corners, or any part of the screen. The 
physical area of clearly defined picture area which would be the "pear 
shape" shown or any other desirable shape, will always be large 
enough to tell its story but need not and should not necessarily fill 
the entire screen area. When the director chooses to use the entire 
screen he will be doing so for special emphasis only. What happens 
with the rest of the screen area that is not being used for clearly defined 
images is very important and it is here that the peripheral-vignette 
idea comes into play. 

For still photography the use of the vignette may be optional and 
be an artistic consideration only. For the motion picture, where it 
may be better to present more realism, the vignette may well be a 
suitable representation of the peripheral portion of our field of vision. 
In real life there is no opaque masking frame in front of us all the 
time. The vignette is more like what one experiences visually. 

In still photography the vignette commonly fades to pure white at 
the extreme edges of a picture. This type of vignette would prove 
disturbing for the motion picture because of the competition created 
by stronger light at the edge of the picture in comparison to the light 
of the important part of the picture. The vignette recommended 
here is one that diminishes the light value toward the edges of the 
picture. Light and color values seem to dim out in the visual 


peripheral. Colors do not change in hue, rather they seem to become 
grayer. The reduced light value proposed for the peripheral vignette 
is also the means of creating a transitional light intensity between the 
bright picture and the picture environment. This development at 
last gives something that will make it possible to eliminate the false 
black masking used around the motion picture. 

Fig. 2 gives a rough ideav of motion pictures as they are presented 
now. There one sees the highly illuminated screen with a contiguous 
black mask. Beyond this mask are the familiar drapes and then the 
decorations usually found beyond this point and farther wall and ceil- 
ing decorations. In addition to the fault of the sharply contrasted 
masking there is the basic fault of the ability of the spectator to be 
particularly conscious of the physical interior and of the depth from 
the picture to his seating position because of the measuring yardstick 
that the wall and ceiling decorations become. It is these faults that 
make the picture appear too small from the rear half of the auditorium 
even though the visual acuity, or ability to discern, may be satisfac- 
tory. It is these faults that do not permit the spectator to have the 
feeling of being close to or even being part of the action which is 

Fig. 3 is a rough sketch showing the enlarged canvas. It may be 
better to call it canvas rather than screen because the cinematog- 
rapher is going to paint his action on that canvas with the freedom 
that an artist wants to express in creating a painting. Research for 
this approach to motion picture presentation can be found in the 
physiological studies by Helmholtz and in much of the research work 
done by some of the famous painters of the Impressionistic School. 
The dotted lines at the picture indicate the present screen size and the 
approximate proposed enlarged size. The shaded tones around the 
picture represent a neutral ceiling and wall-surface treatment com- 
pletely void of decorations. These surfaces have a designed texture 
which reflects just enough of the screen light so as to keep the surface 
near the picture of such a light intensity as will enable them to blend 
with the picture. As these surfaces continue to go away from the 
picture, the texture of the wall is such as to diminish further the 
amount of light reflection from the picture, to come as near as possible 
to what we have in real life, that is, black, which is behind our heads. 
This type of wall surface has been successfully carried out in a great 
many theaters, and is therefore ready for the needed touch in im- 
proved screen presentation. 




Fig. 2 Conventional projection in a conventional auditorium. Blackness 
surrounds the picture and light reflections from the screen outlines the many 
architectural forms of the auditorium. 

Fig. 3 Edges of picture are vignettes. Black masking is omitted. Wall 
and ceiling surfaces are stripped of all distracting architectural forms. 


For immediate application of the idea proposed herein a very simple 
method can be used in producing a suitable film for trial purposes. 
The cinematographer and director of the trial film will anticipate the 
enlarged canvas and will introduce amounts of peripheral vignette 
and shapes of vignette that will heighten the dramatic effect to the 
greatest degree. An artist will paint on a white sheet within a rec- 
tangle of the standard screen proportions, a black-and-white tone 
blended from darkest at the edge to lightest toward center, leaving 
complete white in the main action area. Such tone frames would be 
made for the various picture compositions. The film would then be 
exposed to these blended tones and then be re-exposed in the regular 
manner for the actual picture taking. For interior shots this can be 
accomplished directly with lighting, thereby avoiding the special 
exposures for a vignette masking. The film would then be pro- 
jected on the enlarged screen in the recommended neutral type of 
auditorium. It would be worth noting here the brilliant effects which 
would be achieved in colored film when the colorings toward the 
edges of the picture would come closer to what happens with color in 
the visual peripheral areas. It may then be possible to avoid that 
appearance of a small colored picture postal card sharply contrasted 
with the background. It may even be possible to forget that it is a 
picture one is looking at and thus help to attain the desired illusion. 


(1) B. Schlanger, "On the relation between the shape of the projected picture, 
the areas of vision, and cinematographic technic," /. Soc. Mot. Pict. Eng., vol. 24, 
pp. 402-409; May, 1935. 

(2) B. Schlanger, "Motion picture auditorium lighting," /. Soc. Mot. Pict. 
Eng., vol. 34, pp. 259-264; March, 1940. 

(3) B. Schlanger, "A method of enlarging the visual field of the motion picture," 
J. Soc. Mot. Pict. Eng., vol. 30, pp. 503-509; May, 1938. 

(4) M. Luckiesh and F. K. Moss, "The motion picture screen as a lighting 
problem," J. Soc. Mot. Pict. Eng., vol. 26, pp. 578-591; May, 1936. 

(5) Walter A. Cutter, "The psychology of the theater," /. Soc. Mot. Pict. Eng., 
this issue, pp. 314-322. 

(6) B. Schlanger, "The motion picture theater shape and effective visual recep- 
tion," /. Soc. Mot. Pict. Eng., vol. 26, pp. 128-135; February, 1936. 

(7) Ben Schlanger, "Auditorium light control through surface treatment," 
Better Theaters, Mot. Pict. Herald, April 2, 1938. 

(8) Ben Schlanger, "How function dictates an auditorium style that endures," 
Better Theaters, Mot. Pict. Herald, January 6, 1945. 

Theater Engineering Conference 

Auditorium Design 

Dynamic Luminous Color 
For Film Presentation* 



Summary This paper presents for consideration a departure from the 
usual procedure of planning a motion picture theater, and to consider the 
possibility of designing the appearance of the whole auditorium on the same 
basis as the cinema screen itself is designed, to act as a reflector of light. 

MANY OF us can recall the days .when the cinema screen comprised 
a white surface mounted on a wall with surrounding areas 
painted or otherwise blacked out. There were no curtains or color 
lighting, and projection and screen efficiencies were poor. With the 
development of color-change lighting a new art of presentation began 
to evolve, and it. is with continued development along these lines and 
its effect upon auditorium design that this paper is concerned. 

It may be helpful if certain technical aspects of multicolor lighting 
are first briefly considered. Multicolor lighting equipment will give 
the widest range of results when it includes three circuits correspond- 
ing to monochromatic red, green, and blue lights. Starting with the 
correct hues as primary colors we can employ them in such a way that 
we can match almost any color known. To enable monochromatic 
red, green, and blue lights to match almost any color hue it is neces- 
sary to understand the factors of hue, brilliance, and chroma, the com- 
position of tints and shades, and other factors including simultaneous 
contrast and after images. A brief summary of the former is as follows : 

Hue is the attribute which leads us to describe colors as red, yellow, 
green, blue, and so forth. 

Brilliance is the quality which distinguishes a lighter from a darker 
color by comparison with a surface of known brightness. 

Chroma. With the additive system this concerns the amount of 
white light in a color, a fully saturated color having no content of white 

* Presented October 20, 1947, at the SMPE Convention in New York. 



By specifying these factors it is possible to define any color, tint, 
or shade. Three-color lighting, as just stated, when blended in dif- 
ferent proportions, will provide every desired hue and tint, including 
white, and the value of chroma can be varied because any pure hue 
can be desaturated by suitable proportions of all three primary colors. 
However, in practice it is often better to have a fourth circuit of white 
light, as this enables a number of mixtures to be obtained at a much 
stronger intensity. 

Fig, 1 Type AB Rollocolor lighting controller being operated by the 


To enable the primary colors (and white) to be blended together in 
different proportions it is necessary for each of them to be regulated 
by a brightness control ; and this means four dimmers for each set of 
four-color lighting. Some manual dexterity as well as mental agility 
is required to merge directly from one color mixture to another, be- 
cause having mentally calculated the factors of hue, brilliance, and 
chroma, one has then to manipulate up to four dimmers simulta- 
neously in different directions for every set of lighting equipment with 
only two hands in order to produce the change. My progress in 

376 WILLIAMS April 

color-lighting work was hindered for many years until I had overcome 
this difficulty by a patented form of lighting-control unit, which en- 
abled a person unskilled in color to select and produce a desired hue 
simply by moving a pointer on a dial. This equipment was of the re- 
mote-control type and gave the choice of seventeen carefully selected 
color hues (later increased to twenty-three hues). For many years I 
used this control system extensively and it was supplied to many 
parts of the world. 

After a time a controller was required which would give a greater 
range of color hues, provide the lighting changes at any desired speed, 
and be self-contained so as to be available in portable units. After 

Fig. 2 Color scale of Type AB Rollocolor lighting controller. 

further research a new machine was patented and was an immediate 
success when introduced on the British market. Some papers went 
so far as to say that a revolution had occurred in stagecraft. The 
unit controller provides a much larger range of colors, namely, 50 
colors on the dial. The equipment is portable. When vaudeville 
acts or shows go on tour, the units can be taken around with them. 

After considerable study of lighting conditions in America, the 
author is now concerned in the manufacture here of a new color -mixing 
controller which is based upon new principles, and is the subject of 
new patent applications. 

The new conti oiler will provide a limitless range of color hues. 
The main colors are graded in chromatic order and shown on a con- 
trol scale so that colors corresponding to known tints (such as found 
in the theater gelatine range) can be identified immediately and 


selected. Lesser known colors can be identified by their position be- 
tween known colors. Any color hue can be selected just by moving a 
pointer and the change can be made at any desired speed. In ad- 
dition the over-all brightness of any desired color hue or mixture can 
be obtained at any desired strength, without upsetting the propor- 
tionate values of the primary colors making up the hue. . The bright- 
ness can be selected at the same time as the color hue, or it can be 
varied afterwards. A single dial can control loads of any magnitude 
and the apparatus can be arranged for hand or automatic operation. 
This controller is shown in Fig. 1 and Fig. 2 is an enlarged view of 
the color scale. 

With additive-lighting problems reduced to the selection of any 
known color hue at any desired brightness from apparatus no more 
difficult to operate than a radio set, the mechanics of color mixing are 
behind us, and we are free to operate with luminous color. Since 
luminous -color hues can merge into each other, we are at once faced 
with the fascinating possibilities of order and succession. Entrancing 
as the static-color compositions obtained with paints and dyes can be 
compared to dynamic luminous color they are as photographic stills 
compared to colored motion pictures. Even this analogy is not cor- 
rect, because luminous-color hues are usually much more beautiful 
than paints or pigments and the range of luminous color contains 
many hues quite unknown to most of us. 

The subject of color harmony, contrast, and discord is one which 
few people fully understand, and when this concerns colored light we 
are almost on virgin ground. In the author's textbook The Technique of 
Stage Lighting he has endeavored to give some guidance on this sub- 
ject and has suggested some lines to follow in building up color-light- 
ing compositions. 

The effect of dynamic luminous color on motion picture theater 
showmanship and technique will be very far-reaching ; because more 
than anything else the show is constituted of light, stimulating imagi- 
nation and making people "light-conscious." Colored films are also 
educating people to a sense of color appreciation. 

During the period occupied by these lighting developments; great 
advances have been made with projector and screen efficiency, sound 
has replaced silent pictures, and color has come to the screen. Two 
things have remained unchanged, however: (a) the projection of the 
picture onto a white screen in the middle of a black surround and (6) 
the practice of providing an absolute minimum of auditorium lighting 

378 WILLIAMS April 

during the showing of the pictures. Now these practices came into 
being in the early days of motion pictures when projection and screen 
efficiency were poor, and it may be that they are out of keeping with 
modern technique and methods. 

It is suggested that a screen picture seen against a background of 
luminous color of the right intensity, instead of a black surround, will 
occasion less eyestrain' especially with colored pictures and will have 
sharper definition. Furthermore the area of interest is enlarged and 
if the luminous color is dynamic, i. e., can be changed in hue, then we 
have the means of supporting the film story with an appeal to the eye 
as powerful as is the appeal of background music to the ear. Before 
going any further it is pertinent to quote from a report which followed 
a two-year investigation by a panel of ten experts appointed in 1936 
by the technical committee of the Illuminating Engineering. Society of 
Great Britain 1 to find among other things "whether improvement in 
the present lighting of auditoriums could be made without detriment 
to the screen picture. ..." In the course of their investigations the 
panel carefully considered the effect of an increase of auditorium 
light on the visibility of the pictures presented on the screen and car- 
ried out some very interesting experiments on the brightness and con- 
trast ranges of screen pictures. Their report 1 was published just be- 
fore the war and made recommendations for a much higher standard 
of maintained illumination than is now common in Great Britain; it 
being shown that this would not affect the quality of the projected 
picture. On page 26 the report states "as is now well known the 
acuity and contrast sensitivity of the eye are both improved by suit- 
ably illuminating the surrounds of the central field of vision. With 
completely dark or very poorly illuminated surrounds the contrast 
sensitivity is probably not good enough for the eye to appreciate the 
smallest contrast present in the projected picture." 

Experiments conducted by them showed, for example, that an 
illuminated border pale yellow in color appeared to enhance the con- 
trasts in a black-and-white picture, an effect they attributed to the 
phenomena of spatial induction. They finally reached the conclusion 
that visibility of the picture was improved, and greater visual comfort 
enjoyed, by illuminating the picture surround to a low intensity. 
The author's experience all tends to show that dynamic luminous 
color is the visual equivalent of background music, and properly ap- 
plied and used has tremendous possibilities for increasing the appeal 
of motion pictures. 


It is now recommended hat the screen be provided with a very nar- 
row black edge a few inches in width and be placed in front of a color- 
illuminated area. This area must be completely smooth and so 
lighted that the greatest brightness comes from behind the edges of 
the screen, and then commences to decrease in intensity as it proceeds 
away from the screen. It is important that the screen be silhouetted 
against this color-illuminated area and that the brightness ratios over 
this area are correct, in which case the importance of the screen will be 
emphasized and it will receive dramatic support from the illuminated 

Properly carried out, the screen and illuminated background will 
become one unit with this advantage, namely, the area on which the 
show now takes place (i. e., both screen and surround) can be double, 
or more than double, the size of the screen seen in a black surround. 
The cost of providing the "show" on this additional area is of course 
only a fraction of the cost of that on the screen. 

A particular color hue of the illuminated background can remain 
on for periods long enough for it to become accepted as part of the 
natural scheme of things. Then when it is changed at some dramatic 
moment in the story the new color will have a more powerful effect. 

Just before the outbreak of war an installation on these lines was 
made in Edinburgh, Scotland. Some months. after the opening of the 
theater a letter was received from the owner in which he states that 
"the color effect round the screen has absolutely 'made' our new 
cinema." He goes on to say that "This week we were showing a re- 
issue of Whoopee in technicolor, and the effect was wonderful . . . the 
lighted screen changing to blend or contrast with the various color 
sequences . . . just puts this Eddie Cantor film up 50 per cent in enter- 
tainment value.." 

It seejns probable that the general public will become educated to a 
greater sense of color appreciation through this method of associating 
color with specific moods and values and this in turn will enable them 
to ob*tain more enjoyment out of colored motion pictures. 

In the Edinburgh installation the background lighting was con- 
trolled from color-mixing apparatus of the first type described in this 
paper, but in this case the control was finally vested in a row of small 
tab keys mounted on each projector in the bioscope room. The keys 
were marked not only with the color hue they would each produce if 
pressed, but also with the name of a specific mood, as for example : 
danger red light; warmth and contentment orange; kindness 

380 WILLIAMS April 

pale green; sinister peacock blue; delicate emotion violet. By 
reducing the mechanics of color mixing to this simple system we were 
able to obtain excellent results from the usual staff. 

Prior to the war I was developing a system of. decorative reflective 
effects from concealed color lighting, which introduced new conven- 
tions of decorative treatment, expressive of the conception of dynamic 
luminous color. 

In a large concert hall in Britain, the proscenium opening is 60 feet 
wide. The large center feature is lighted very evenly, although there 
is not a lamp in this ceiling. The lighted-ceiling effect is reflected 
light. The lighting is projected from the cornices at the sides of the 
room, and the contours of the enrichments are calculated so that they 
gleam by reflected light. If we throw, say, a red light from one side 
and a green light from the other side, we cause compound-color re- 
flections and we have a less expensive installation. There is no wiring 
to install, and we do not have any electrical maintenance troubles for 
this ceiling. 

In Fig. 3, the vertical columns which form the sides of the stage 
opening were designed with special horizontal flutes in the plaster, so 
that they gleam when lighted. The designs on the face of the archi- 
trave were also contoured so they light up by reflection. The exits 
are between these columns, and they are kept lighted during the show. 
The horizontal lines on the side walls also light up by reflection. The 
black-and-white shading seen in the picture represents different 

At the Carlton theater in Dublin the large plaster domes in the 
ceiling light up only by reflection; there are no lamps in them. The 
complex features on the walls, on each side of the proscenium opening, 
are also contoured and silvered, and each detail lights up with com- 
pound-color reflections, when different colored light is thrown into 
them from different directions, so you have decorations painted in 

There is a motion picture theater in a small mining village in South 
Wales, just a few miles 'from Swansea where the traditional picture- 
frame proscenium is gone, and the new surround is lighted by reflec- 
tion. There are no lamps in it. The lighting equipment is concealed 
mainly in the stage and partly in the balcony and on the back wall of 
the auditorium. 

In one of J. Arthur Rank's theaters, the stage sweeps across, but 
instead of the side of the stage going straight down, it curves around, 




coming down behind dummy side walls, so as to make the whole pro- 
scenium opening wider. This decorative area is made of plaster. 
The circular cups are very carefully contoured and silvered, and each 
one gives you a mosaic of reflective points. When the color lighting 
was left on during the showing of pictures, the effect was tremendous, 
so much so that I believe Mr. Rank's engineers are considering some- 
thing on these lines for the whole theater circuit. 

The same idea was developed a little bit further in one of the largest 
motion picture theaters . in Britain. Th'e proscenium top sweeps 

Fig. 3 Auditorium of motion picture theater in North Wales designed for 
"decoration with light." Architect, S. Colwyn ssoulkes. 

around and comes down behind the dummy side walls. We put all 
the stage controls behind one of these walls, including the switch- 
board, so that the stage staff can look into the show and can watch it 
in just the same way as the public, which eliminates mistakes and en- 
ables much more ingenious lighting effects to be carried out. 

In halls of this nature it is possible to provide, by a secondary and 
low-intensity system of multicolor floodlighting, a soft, dim, general 
illumination of the walls and ceiling of the auditorium itself, during 
the showing of the pictures. This lighting can change in color and 
give dramatic support to the story without glare spots or anything 
else to cause distraction. It may be thought that lighting up the 

382 WILLIAMS April 

auditorium is a sufficient distraction in itself, but this is not the case, 
because decorative features and the degree of brightness and color of 
the lighting are all designed to lead the attention to the screen. In 
this way the dramatic value of the auditorium changes in harmony 
with the screen background, and the audience has the feeling of par- 
ticipating in the show instead of watching it from outside. 

Apart from the dramatic values, people entering the theater from 
the daylight will be able to see their way easily and safely to their 
seats without the use of hand torches, and better lighting will be avail- 
able in the case of emergency. This can be done without detriment 
to the quality of the picture, as has been shown by the British report 
already mentioned. 

With color-change-maintained lighting it is necessary to provide 
foolproof means to ensure that all circuits cannot be dimmed out at 
the same time. Also it is desirable that both background and hall 
lighting be operated from the same control. 

It will be evident that if there have been problems to overcome in 
order to produce desired single-color hues, there are additional prob- 
lems when relating a number of different hues in a composite-color 
arrangement. These problems are in fact very great, but I believe 
that the new controller now being produced will give the complete 
answer to these difficulties. 

The controller (Fig. 1) will not only give complete freedom of choice 
concerning individual color hues, but can enable hues from one set of 
lighting equipment to be grouped with different Hues from other light- 
ing equipment in composite arrangements. These composite arrange- 
ments can be set up or changed as desired, and can be operated from a 
single control dial. Thus selection of the dominant color will also 
cause all the supporting colors in a color composition to come on at the 
same time. 

The results are always the same each time the controller is operated, 
so in the case of circuit theaters it will be possible at headquarters to 
work out a lighting plot for a particular picture and then to send out a 
simple cue sheet to the various theaters. All that the local staff has 
to do after making certain adjustments at the beginning of the run of a 
picture, is to move a pointer on a scale at each cue, and the controller 
will do the rest. 

There is no limit to the number of cues that may be given and no 
restriction as to color hues, in fact the range of available colors is much 
wider than the entire range of theater gelatines. 


It is not believed that we have by any means reached the ultimate 
in fundamental auditorium design, and the theaters which have been 
illustrated are only intended to indicate certain trends of design. 
The author thinks that the future fundamental design for a motion 
picture auditorium should be one in which all conventional methods 
of decoration are omitted, and the hall is created for "decoration with 
light." There should be no proscenium frame, but the screen should 
stand on its own with a very narrow margin of black edging, and be 
boldly silhouetted against a plain white background which curves 
round and merges into the walls and ceiling of the hall without a 
break. The areas in front of, around, and behind the screen would 
thus be unified into one set of surfaces, and the whole of them would be 
revealed by dynamic luminous color. The lighting would be bright- 
est on the area behind the screen, so as to create a kind of aura behind 
its edges, and as the illumination spreads out toward the seating it 
would diminish and merge into other areas of differently colored light. 

During intervals the lighting and color values would include the 
screen just as another white surface in the composite design. During 
the showing of pictures, however, the whole of the lighting conditions 
would be subordinated to the screen picture and would be arranged to 
provide the best conditions for visual comfort and picture definition 
as well as to provide dramatic visual values for .the greater enjoy- 
ment of the story. 

With this conception the motion picture theater would be com- 
pletely and logically expressive of what the screen picture really is, an 
appeal to the eye in terms of contrasts of light, shade, and color. 


(1) H. C. Weston and E. Stroud, "The lighting of cinema auditoriums for 
visibility and safety," Trans. Ilium. Eng. Soc. (London), 1939; presented January 
10, 1939, Illuminating Engineering Society of Great Britain. 


CHAIRMAN JOHN EBERSON: What does the audience believe about a very in- 
teresting innovation of the treatment of color and control which you are looking 
for in respect to screens, stage, auditorium, side walls, and ceilings? 

MR. LESTER B. ISAAC: For years we have been trying to eliminate extraneous 
light in motion picture auditoriums. I am surprised that someone would try to 
induce or introduce extraneous light. It is true, we of the motion picture business 
are selling light, but only that light which represents the projected image on the 
screen. Any other light that serves to interfere with that projected light, which 

384 WILLIAMS April 

is our screen image, certainly will cause the audience much discomfort. The eyes 
only accept so much light at one time, and a reasonable color or hue. To add any 
additional colors in addition to what is on the screen, will cause the iris of the eye 
to do gymnastics. 

We admit that our auditoriums are not perfect, but we are trying to correct 
that. We are endeavoring to eliminate the use of all types of lamps from wall 
brackets, particularly those in the red family, or in the red spectrum, so that 
they do not injure the eye or interfere with the projected image. 

The use of color borders is nothing new in this country. It was tried many 
years ago, as far back as 1919, when we used red, blue, and green borders. Be- 
fore that, D. W. Griffith, the great picture director and producer, also thought he 
was an expert in lighting. In an attempt to add atmosphere to several of his 
pictures, and one I remember in particular was "Broken Blossoms," he introduced 
the use of the so-called X-ray lamp, which was on the side, top, and bottom of the 
screen. Through various scenes it would project either red, or a magenta, or a 
blue, or a green. 

These additional colors certainly only added to the distraction and the discom- 
fort of the audience. I should dislike to see what would happen to a technicolor 
picture with this color projected; the audience trying to concentrate on a moving 
object on the screen, and this changing light source at the same time. 

I feel that the black stands out naturally. It has proved the best method that 
we have today of cutting off the extraneous light that may hit the screen. It also 
helps us to frame out distortion, which is caused by the booth's being constructed 
in the highest and most rear part of the theater. This is not the present-day 
method, but, unfortunately, in the great majority of theaters in the United States 
today the booth has that vertical pitch. That is why the black border is very 
convenient today, and I think it will continue to be so until some other method 
has proved much better. 

I, personally, am opposed to any color light whatsoever that may interfere 
with the projected image on the screen, black or white, or any color. 

Mr. R. GILLESPIE WILLIAMS: I was not recommending a border around the 
picture. I was recommending that the picture stand in front of an illuminated 
background and be silhouetted against it. Furthermore, I was under the impres- 
sion that I was making a case, that under the proper lighting, people will see the 
picture better. I take it that Mr. Isaac has no objection to the public's seeing 
more detail of the picture than it has hitherto seen. 

I have here a report which took a committee of experts two years to prepare. 
It is a detailed affair which gives conclusive scientific support for what I have just 
said, and proves that if lighting areas around the screen are properly employed, 
and I must emphasize that, the eye sees more detail in the picture than it has 
ever seen before. 

Furthermore, I am going to make this statement authoritatively: that if you 
use the right contrasting colors around a Technicolor picture, you will have a 
greater appreciation of the colors in it than ever before. 

In the motion picture industry nearly every innovation that is not directly con- 
cerned with film and film apparatus is usually opposed by the slogan that "the 
public pays to see the picture." I will rest my case on that statement: that the 
public pays to see the picture. The recommendations I have suggested will 


enable the public to see the picture better. There will be less eyestrain, and there 
will be greater contrasts in the tones which make up the picture, and the color 
visibility will be improved. 

This report, by the way, reduced to some simple rule-of-thumb formula, rather 
established a ratio of 200 to 1 between the brightness of the light falling on the 
screen (from the projector without a film or shutter) and the illumination of sur- 
rounding areas. However, on the other hand, the black border, which Mr. Isaac 
was defending, is bad for the eye. 

You are asking people to sit in a dark hall and to stare at a brightly lighted 
white area, included in a fairly narrow angle of vision with the pupil of the eye 
trying to adjust itself to a brightly lighted area while in the same field of vision 
there is a large area of dead black. What is the eye to do? Is the pupil to open 
up for the black or close down for the brightly lighted area? The result is that it 
compromises. By trying to balance between dead black and bright white (which 
are the high lights of the picture), it does not see the subtle half tones, which are 
in the picture all the time. You are making it impossible for the eye to see them. 

However, just lighting up a border around the screen or merely putting light on 
in the hall does not necessarily do what I have just said. It must be worked out 
scientifically. If it is properly done, and I have done it, you see more than you 
would otherwise see with a black surround. I think that is, after all, the general 
idea of what the screen is for. 

MR. BEN SCHLANGER: Let us decide what the problem is if there is one. 
There is a problem. These effects actually have been tried. In the Roxy Theater 
you had a fixed intensity illuminated border for several months. I tried an illu- 
minated border for a year in a theater up on Broadway and 95th Street. They 
were all unsuccessful, because any illumination around the picture which is not 
synchronous with the particular intensity or hue of color of the frame of picture 
being shown is as disturbing as a black border. 

Consequently, after years of trying to solve this problem, I have at last 
come to the conclusion that its solution lies in what Hollywood does. A solution 
which necessitates having cue sheets and color effects, where one theater may do it 
a little better than the other theater, where it is left to chance, to some 
artist who thinks purple will be good for glamour, or whatever it is, is a dangerous 

If you can have a simple solution, I think, like the one I presented here today, 
then it is much easier to go to some dim tint of light that is on the walls. When I 
say a dim tint of lights beyond the picture, it is not secondary illumination. It is 
probably 1 /ioo or 1 /i 6 o of the light intensity of the picture coming off as a reflected 
light from the walls. That is inexpensive to do. You do not have any lighting ex- 
pense whatsoever. You do not have any cue sheets. You just project your pic- 
ture and you are through. 

There is a great deal of material on this subject in printed form. A test was 
made about seven or eight years ago in which this Society actually tested inten- 
sity of light around a picture. It is true, Mr. Williams is right, that black around 
the picture has been found disturbing by test. We agree on the problem that 
exists, but not on his solution. 

MR. WILLIAMS: Mr. Schlanger, if you take a Technicolor picture and you wish 
the people to get the greatest sense of color out of it, you want to show that picture 

386 WILLIAMS April 

against a field with a very low intensity of light, which is the correct contrasting 
color to the dominant color of the particular* scene. 

If you take the colors off that Technicolor picture and add them all together, 
as you would do if you were to take reflected light from the screen, or as we have 
done in Britain, having a special lens made, and blowing out the edges of the pro- 
jected picture so the edges of the picture spread out, you get white light all the 
time, because you are adding with the "additive" system. If the Hollywood color 
expert had done his job properly, he would have obtained color harmony in the 
picture. When he has color harmony he has probably balanced his colors. If he 
has balanced his colors, you have white: when the various hues are superimposed 
by reflection can you get that color contrast? 

I had a lecture demonstration outfit in England, with which I can show a sur- 
face lighted with ordinary white light. I can then show how it becomes a vivid 
green, or a vivid mauve, or blue, or red, or orange, or any color you like, by chang- 
ing the lighting conditions which you see in the vicinity. The actual lighting of 
this surface never changes. I induce the colors in the eye by the right seeing 
conditions. Now if there is a scene on the screen in which fundamentally, the 
dominant color is yellow, I should do that, obviously, by putting a lot of blue in. the 
vicinity to make the eye induce yellow. 

I am not suggesting that we are so clever yet that we can change the lights all 
the time for every scene, but most important pictures have a few high spots in the 
story which are worth emphasizing, about six or eight times in the feature picture. 
Those can be cued up and done easily. 

I was told by someone that he saw a demonstration, I think, in Universal 
Studios in 1936 in which the same scene was shown up several times with different 
types of background music. The effect the background music made was really 
remarkable. It completely changed its value. We accept background music 
when we see a talking motion picture as a convention. Why cannot we accept 
color as another convention? 

You are dealing with the eye. The fact is that everything we see is an image of 
light which takes place in the eye. It is not in the screen. The picture we see is 
in the eye. All that comes off the screen are invisible light rays and invisible 
light rays come into the eye and become vision in the eye. What you see is just 
largely a matter of seeing conditions. If you master seeing conditions, you can 
induce or help to induce the picture in the eye, and make it better or make it 

MB. SCHLANGER: I am afraid if you were trying to get an effect of what hap- 
pens in real life and in real life we see in color I do not think as we go about in 
real life that we have a purple or any other complementary color frame around 
what we are viewing. It is safer not to have any kind of a frame beyond the pic- 
ture that you are looking at, be it color or be it anything else. I think we have 
to just be able to look at just a scene ahead of us, with no distraction whatsoever. 

MR. MATTHIAS RADIN : I have operated chains of theaters throughout the United 
States, but the type of theater I ran was similar to the Cameo Theater in New 
York. I think the audiences that we had there were the most critical audiences in 
this country. We have tried the color proposition that you discuss, but we tried 
it the same way as you said, and not as Mr. Williams recommends, because we did 
not have the facilities for blending the color. All that we had to use upstairs was 


a gelatine that the operator thought he would use, and had no conception of what 
he was doing. 

It is a very easy thing for an architect, who has not actually operated theaters 
365 days a year, to tell you how this picture should be presented and what it 
should not be, and that it detracts from the principles of the original producers. 

However, I learned one thing: when I went to college, we had a music-appre- 
ciation class, for the reason that the greater percentage of boys who attended the 
college had no idea of the classics. They did like jazz. In those days they did not 
call it jazz, but they liked that type of music. After the students had been taught' 
the beauty and the very fine things that come from musical classics, there was an 
appreciation so that when the boy heard that classic in the future he appreciated 
it. If he did not get it, he missed it. 

The same proposition applies to those who may go to an art gallery. We go to 
the Louvre and w^ stand there, and I pass on in two minutes. Another man will 
stand there for an hour and view one particular picture, because he has been 
taught the appreciation and the beauty of that art. 

If the motion picture theater tea'ches people to appreciate high-class music, as 
we are doing today, and also understand the beauty of light, its effects, SQinething 
new brought into that theater, and when that appreciation has been cultivated by 
the people, it will add to instead of detract, if done properly. That is the main 
thing that Mr. Williams talks about. 

MR. LAWRENCE COHEN: What is the purpose and need of the black border, 
small as it is, around the screen? 

MR. WILLIAMS: That is to cover the ragged fringe of the picture, the light pic- 
ture, which you always get on the screen. A five-inch black border will just 
cover that ragged edge. Furthermore, from an artistic point of view, it really 
looks very well. 

MR. COHEN: It was a little distracting to me, because of the fact that it was 
between the color and the picture. 

MR. WILLIAMS: The lantern slide actually was a composite picture made up 
afterward. I think the black border was painted in. The screen was about 26 
feet wide, and the five-inch black border around it would not be quite so visible 
as it was in that slide. 

MR. COHEN: Would it not be possible to compromise between color, as you 
describe it, and Mr. Schlanger's idea by illuminating the background and elimi- 
nating the black border? 

MR. WILLIAMS: Theoretically, yes, but only if the projected picture could 
exactly end at the edge of the screen, I believe, which is not possible in practice. 

I do not think it would be practical politics, if we do not have such con- 
trol of the color lighting adjacent to the screen, that we can cause immediately 
the background lighting to the screen, and perhaps the whole environment of the 
hall to merge slowly into a new composition, selected from a number decided by 
experts in the first place. 

Most managers see a picture through at least once a week. It is not difficult 
to take an envelope out of your pocket, and jot down a note, when an airplane is 
powerdiving to death, and you do not think the hero is going to get out, and the 
background is a ta-ta-ta-ta, and you are excited and frightened, so that later you 
tell the operator to put a finger on key No. 6 at that point. That is all he has to do. 


In that way you can cue on the back of an envelope three or four points in the 
picture. The thing becomes practical politics. I assure you it would not be- 
come practical politics if the operator had to stand on one foot and use his hands 
and knees to try some color mixing. 

MR. SCHLANGER: I have actually, experimented with trying to do away with 
that narrow black border. As Mr. Williams says, that narrow black border is the 
means of absorbing the fuzzy edge of a projected picture. Three inches might be 
all right for a small screen where there is not a steep projection angle, but if you 
'have a steep projection angle three inches is not enough. However, this is all 
beside the point. I feel the narrow black border is just as bad as a wide black 
border. If I must have it, I am in favor of a wide black border, because in order 
to have a white picture and a black border and the light necessary, another con- 
trasting value is disturbing. Until the time I see a complete solution to a proper 
blending from the picture out to its surroundings, I would be jusff as willing to have 
black as anything else. 

Theater Engineering Conference 

Auditorium Design 

The New Slide-Back Chair* 



Summary The need for a retractable chair in theaters, and the features 
that should be embodied in a chair of this type are outlined. 

WHY THE necessity for a retractable chair? In the author's expe- 
rience in the seating business, which goes back some twenty-five 
years or more, the big problem has been, how can the necessity of 
standing up to allow others to pass between the rows of chairs in a 
theater be eliminated. In an overwhelming majority of theaters, the 
space between the rows of chairs is so narrow that it is absolutely 
necessary to stand up to let others pass, and when a person has a hat, 
overcoat, and perhaps a bundle or two on his or her lap, it becomes 
quite a problem to stand up, let alone allowing someone to pass. 

There are two ways of eliminating this inconvenience. One 
method is by spacing the rows far enough apart so that there will be 
ample room for people to get through without the occupant of the 
chair having to stand up, or use a retractable chair that will serve the 
same purpose. 

The seating industry, which has been faced with this problem, has 
devoted years of research and experimentation in trying to overcome 
this problem, and this is what has been found. In order to achieve 
the desired effect it has been found that chairs would have to be 
spaced at least 40 inches back to back to allow passage without body 
contact. On a spacing of 36 inches back to back, it was found that it 
was possible to pass with some difficulty. This, of course, was out of 
the question in most of the cases; the loss of seating capacity would 
not permit such practice. -The demand is always for more capacity 
even at the expense of discomfort to the theater patron. 

Now comes the retractable chair. In this research, all types of 
human models, both male and female were used, and the conclusion 
* Presented October 20, 1947, at the SMPE Convention in New York. 


390 GEDRIS April 

was reached that the average size of theater patrons is as follows: 
males 5 feet 7 inches in height, weight 165 pounds, females, 5 feet 4 
inches in height, weight approximately 130 pounds. One can readily 
appreciate that chairs must be manufactured to fit the average size per- 
son. Using a man 5 feet 8 inches tall, weighing 170 pounds as a model, 
which is above average, it was found that there was more passing 
room with retractable chairs spaced at 32 inches back to back than 
with stationary chairs spaced the same distance with the occupant 
standing. There was more passing room with less body contact. 
It was also found that this same spacing of 32 inches back to back us- 
ing retractable chairs gave more passing room than with the station- 
ary chairs spaced 36 inches back to back with the chairs occupied. 
These facts concerning retractable chairs should be very interesting 
to the theater owner, as its enables him to put in the maximum num- 
ber of chairs and still give his patrons more comfort than if he had 
used stationary chairs spaced at 36 inches back to back. Another 
interesting discovery is that there is more passing room with the re- 
tractables at 34 inches back to back than with the stationary chairs 
at 40 inches back to back. The same result was obtained using as a 
model a girl 5 feet 6 inches tall, weighing 120 pounds. The retrac- 
table chairs used in these experiments had a retraction of 6 inches. 
During the past twenty-five years or more, numerous develop- 
ments in retractable chairs have been patented only to be found im- 
practical or so lacking in the necessary mechanical requirements that 
'they were discarded. Some of these were absolutely fantastic. 
There is one outstanding example. In 1931 in Los Angeles a man 
showed something he had developed that he thought would revo- 
lutionize the entire seating industry. The device worked something 
like this. Two rows of chairs are fastened to a traveling conveyor 
much like a merry-go-round, which travels around at the push of a 
button. The usher brings two patrons down and seats them, pushes 
a button, and slides them over a couple of seats. This goes on until the 
two rows are filled. When a person wants to leave, he pushes a but- 
ton and the "chairs travel around until his chair arrives at the aisle. 
He then can get out without disturbing anyone. Now mind you, the 
inventor had taken out a patent on this device, which he was sure 
would revolutionize the seating industry. When asked what he 
figured the cost would be, he thought that it would cost about $75.00 
per chair. This was back in 1931 at a time when a good theater 
chair was selling for around $10.00. 


The second question that presents itself is, "what are we to expect 
in a retractable chair?" The following enumerates some of the things 
that should be embodied in a chair of this type to insure durability, 
comfort, safety, and years of troublefree service. 

1. Ease of operation. The retractable chair should be so designed 
and constructed that the seat will move back on a horizontal plane 
smoothly without hindrance, and with the least amount of effort on 
the part of the occupant of the chair. 

2. The retractable chair should embody an automatic retracting 
device that automatically retracts the chair when the occupant stands 
up to leave. This device should retract the chair slowly and smoothly 
without bumping or jarring the mechanism. 

3. The retractable chair should embody a seat-lifting device 
which lifts the seat as the chair is retracted, to an angle of approxi- 
mately 45 degrees. This leaves the seat in a position so that the 
occupant can sit down without the necessity of holding the seat down 
with his hands as he occupies the chair. With the chair retracted, 
and the seat raised, this leaves the space between rows free of any 
obstruction, which is a big safety factor in case of emergency and also 
eliminates the necessity of raising the seats when cleaning under the 

4. The retractable chair should embody the ultimate in relaxing 
comfort. This can be achieved by perfect posture, which is brought 
about through the proper relationship of the back to the seat, and by 
the use of deep spring cushions in the seat, and the proper padding of 
the back. The back should be so constructed that it completely 
covers the back of the seat, thus preventing the person sitting in the 
row in back from using the seat as a foot rest. The bottom edge of the 
back should be so designed as to eliminate sharp edges that might 
bump the shins of the person in the next row as the chair is retracted. 

5. The retractable chair should be so constructed that it will not 
require oiling, greasing, or other maintenance. The fact that this 
type of chair has more moving parts than the stationary chair should 
by no means mean that it will require more care than any other type 
of chair. On the contrary, the retractable chair should and can be 
built with oilless bearings that need no oil and will give troublefree 
service for years without any maintenance whatever. 

6. The retractable chair should have no obstructions in its under- 
structure that will in any way hinder cleaning under the chair. 

7. The retractable chair should be designed and constructed so 


that it will embody the flexibility required to compensate for floor 
conditions that are encountered, and to facilitate the installation of 
the chair. 

8. For reupholstering purposes, the retractable chair should be so 
constructed that the upholstered parts can be removed from the chair, 
recovered and replaced with the least amount of effort, and without 
the need for specialized mechanics to do the job. 

Finally, there is no reason why the retractable chair should not be 
just as attractive in style and design as the most modern conven- 
tional-type theater chair. 

The retractable chair has proved itself and is definitely here to stay. 
The yearly increase of this type of seating compared to the total of 
chairs manufactured will be so marked, that at the end of a few years, 
the retractable-chair sales will pass those of the conventional type. A 
theater with a conventional-type chair, except in the balcony, will be 
as obsolete as a car without a self-starter. 

Officers of the Society 








J 948-1949 

Officers of the Society 


Convention Vice-President 



Engineering Vice-President 


Financial Vice-President 



Editorial Vice-President 



Executive Vice-President 


Governors of the Society 











Officers and Managers of Sections 




W. H. RIVERS, Chairman 
JAMES FRANK, JR., Past-Chairman 
EDWARD SCHMIDT, Secretary-Treasurer 




R. T. VAN NIMAN, Chairman 

A. SHAPIRO, Past-Chairman 

G. W. COLBURN, Secretary-Treasurer 




S. P. SOLOW, Chairman 

W. V. WOLFE, Past-Chairman 

G. R. CRANE, Secretary-Treasurer 










Secretary- Treasurer 


Constitution and Bylaws of the 
Society of Motion Picture Engineers 


Article I 


The name of this association shall be 

Article II 

Its objects shall be: Advancement 
in the theory ahd practice of motion 
picture engineering and the allied arts 
and sciences, the standardization of the 
equipment, mechanisms, and practices 
employed therein, the maintenance of a 
high professional standing among its 
members, and the dissemination of 
scientific knowledge by publication. 

Article III 

Any person of good character may be 
a member in any grade for which he is 

Article IV 

The officers of the Society shall be a 
President, a Past-President, an Execu- 
tive Vice-President, an Engineering 
Vice-President, an Editorial Vice- 
President, a Financial Vice-President, 
a Convention Vice-President, a Secre- 
tary, and a Treasurer. 

The term of office of all elected 
officers shall be for a period of two 
years. Of the Engineering, Editorial, 
Financial, and Convention Vice-Presi- 
dents, and the Secretary, and the 

*Corrected to April 1, 1947. 


Treasurer, three shall be elected al- 
ternately each year, or until their suc- 
cessors are chosen. The President 
shall not be immediately eligible to 
succeed himself in office. Under such 
conditions as set forth in the Bylaws, 
the office of Executive Vice-President 
may be vacated before the expiration 
of his term. 

Article V 


The Board of Governors shall con- 
sist of the President, the Past- Presi- 
dent, the five Vice-Presidents, the 
Secretary, the Treasurer, the Section 
Chairmen, and ten elected governors. 
Five of these governors shall be resident 
in the area operating under Pacific 
and Mountain time, and five of the 
governors shall be resident in the area 
operating under Central and Eastern 
time. Two of the governors from the 
Pacific area and three of the governors 
from the Eastern area shall be elected 
in the odd-numbered years, and three 
of the governors in the Pacific area and 
two of the governors in the Eastern 
area shall be elected in the even- 
numbered ye.ars. The term of office of 
all elected governors shall be for a 
period of two years. 

Article VI 



There shall be an annual meeting, 
and such other meetings as stated in 
the Bylaws. 

VOLUME 50 397 




Article VII 


This Constitution may be amended 
as follows: Amendments shall be ap- 
proved by the Board of Governors, and 
shall be submitted for discussion at any 
regular members' meeting. The pro- 
posed amendment and complete dis- 
cussion then shall be submitted to the 
entire Active, Fellow, and Honorary 
membership, together with letter ballot, 
as soon as possible after the meeting. 
Two thirds of the vote cast within- 
sixty days after mailing shall be re- 
quired to carry the amendment. 


Bylaw I 

SEC. 1 The membership of the 
Society shall consist of Honorary mem- 
bers, Fellows, Active members, Asso- 
ciate members, Student members, and 
Sustaining members. 

An Honorary member is one who has 
performed eminent services in the ad- 
vancement of motion picture engineer- 
ing or in the allied arts. An Honorary 
member shall be entitled to vote and 
to hold any office in the Society. 

A Fellow is one who shall not be less 
than thirty years of age and who shall 
comply with the requirements of either 
(a) or (b) for Active members and, in 
addition, shall by his proficiency and 
contributions have attained to an out- 
standing rank among engineers or ex- 
ecutives of the motion picture industry. 
A Fellow shall be entitled to vote and 
to hold any office in the Society. 

An Active member is one who shall 
be not less than 25 years of age, and 
shall be (a) a motion picture engineer 
by profession. He shall have been en- 
gaged in the practice of his profession 
for a period of at least three years, and 
shall have taken responsibility for the 

design, installation, or operation of 
systems or apparatus pertaining to the 
motion picture industry; (b) a person 
regularly employed in motion picture 
or closely allied work, who, by his in- 
ventions or proficiency in motion pic- 
ture science or as an executive of a 
motion picture enterprise of large 
scope, has attained to a recognized 
standing in the motion picture in- 
dustry. In case of such an executive,, 
the applicant must be qualified to take 
full charge of the broader features of 
motion picture engineering involved in 
the work under his direction. 

An Active member is privileged to 
vote and to hold any office in the 

An Associate member is one who 
shall be not less than 18 years of age, 
and shall be a person who is interested 
in or connected with the study of motion 
picture technical problems or the ap- 
plication of them. An Associate mem- 
ber is not privileged to vote, to hold 
office, or to act as chairman of any 
committee, although he may serve 
upon any committee to which he may 
be appointed; and, when so appointed, 
shall be entitled to the full voting privi- 
leges of a committee member. 

A Student member is any person 
registered as a student, graduate, or 
undergraduate, in a college, university, 
or educational institution, pursuing a 
course of studies in science or engineer- 
ing that evidences interest in motion 
picture technology. Membership in 
this grade shall not extend more than 
one year beyond the termination of the 
student status described above. A 
Student member shall have the same 
privileges as an Associate member of 
the Society. 

A Sustaining member is an individ- 
ual, a firm, or corporation contribut- 
ing substantially to the financial sup- 
port of the Society. 




SBC. 2 All applications for member- 
ship or transfer, except for Honorary 
or Fellow membership, shall be made 
on blank forms provided for the pur- 
pose, and shall give a complete record 
of the applicant's education and ex- 
perience. Honorary and Fellow mem- 
bership may not be applied for. 

SEC. 3 (a) Honorary membership 
may be granted upon recommendation 
of the Board of Governors when con- 
firmed by a four-fifths majority vote of 
the Honorary members, Fellows, and 
Active members present at any regu- 
lar meeting of the Society. An Hon- 
orary member shall be exempt from all 

(b) Fellow membership may be 
granted upon recommendation of the 
Fellow Award Committee, when con- 
firmed by a three-fourths majority vote 
of the Board of Governors. Nomina- 
tions for Fellow shall be made from the 
Active membership. 

(c) Applicants for Active member- 
ship shall give as references at least one 
member of Active or of higher grade in 
good standing. Applicants shall be 
elected to membership by the unani- 
mous approval of the entire member- 
ship of the appropriate Admissions 
Committee. In the event of a single 
dissenting vote or failure of any mem- 
ber of the Admissions Committee to 
vote, this application shall be referred 
to the Board of Governors, in which 
case approval of at least three fourths 
of the Board of Governors shall be re- 

(d) Applicants for Associate mem- 
bership shall give as references one 
member of the Society in good stand- 
ing, or two persons not members of the 
Society who are associated with the in- 
dustry. Applicants shall be elected to 
membership by approval of a majority 
of the appropriate Admissions Com- 

(e) Applicants for Student member- 
ship shall give as reference the head of 
the department of the institution he is 
attending, this faculty member not 
necessarily being a member of the 

Bylaw II 

SEC. 1 An officer or governor shall 
be an Honorary, a Fellow, or an Active 

SEC. 2 Vacancies in the Board of 
Governors shall be filled by the Board 
of Governors until the annual meeting 
of the Society. 

Bylaw III 


SEC. 1 The Board of Governors 
shall transact the business of the 
Society between members' meetings, 
and shall meet at the call of the Presi- 
dent, with the proviso that no meeting 
shall be called without at least seven 
(7) days' prior notice, stating the pur- 
pose of the meeting, to all members of 
the Board by letter or by telegram. 

SEC. 2 Nine members of the Board 
of Governors shall constitute a quorum 
at all meetings. 

SEC. 3 When voting by letter 
ballot, a majority affirmative vote of 
the total membership of the Board of 
Governors shall carry approval, ex- 
cept as otherwise provided. 

SEC. 4 The Board of Governors, 
when making nominations to fill 
vacancies in offices or on the Board, 
shall endeavor to nominate persons who 
in the aggregate are representative of 
the various branches or organizations 
of the motion picture industry to the 
end that there shall be no substantial 
predominance upon the Board, as the 
result of its own action, of representa- 
tives of any one or more branches or 
organizations of the industry. 




Bylaw IV 

SEC. 1 All committees, except as 
otherwise specified, shall be appointed 
by the President. 

SEC. 2 All committees shall be 
appointed to act for the term served 
by the officer who shall appoint the 
committees, unless their appointment 
is sooner terminated by the appointing 

SEC. 3 Chairmen of the committees 
shall not be eligible to serve in such ca- 
pacity for more than two consecutive 

SEC. 4 Standing committees of the 
Society shall be as follows to be ap- 
pointed as designated: 

(a) Appointed by the President and 
confirmed by the Board of 

Progress Medal Award Com- 

Journal Award Committee 
Honorary Membership Com- 

Fellow Award Committee 
Admissions Committees 
(Atlantic Coast Section) 
(Pacific Coast Section) 
European Advisory Com- 
(6) Appointed by the Engineering 

Vice- President 
Sound Committee 
Standards Committee 
Studio Lighting Committee 
Color Committee 
Theater Engineering Com- 

Exchange Practice Com- 
Nontheatrical Equipment 

Television Committee 
Test Film Quality Com- 

Laboratory Practice Com- 

Cinematography Committee 

Process Photography Com- 

Preservation of Film Com- 

(c) Appointed by the Editorial V ice- 

Board of Editors 
Papers Committee 
Progress Committee 
Historical Committee 
Museum Committee 

(d) Appointed by the Convention 

Vice- President 
Publicity Committee 
Convention Arrangements 


Apparatus Exhibit Com- 

(e) Appointed by the Financial 

Membership and Subscrip- 

SEC. 5 Two Admissions Commit- 
tees, one for the Atlantic Coast Section 
and one for the Pacific Coast Section, 
shall be appointed. The former Com- 
mittee shall consist of a Chairman and 
six Fellow or Active members of the 
Society residing in the metropolitan 
area of New York, of whom at least 
four shall be members of the Board of 

The latter Committee shall consist of 
a Chairman and four Fellow or Active 
members of the Society residing in the 
Pacific Coast area, of whom at least 
three shall be members of the Board of 

Bylaw V 

SEC. 1 The location of each meet- 
ing of the Society shall be determined 
by the Board of Governors. 




SEC. 2 Only Honorary members, 
Fellows, and Active members shall be 
entitled to vote. 

SEC. 3 A quorum of the Society 
shall consist in number of one fifteenth 
of the total number of Honorary mem- 
bers, Fellows, and Active members 
as listed in the Society's records at the 
close of the last fiscal year. 

SEC. 4 The fall convention shall be 
the annual meeting. 

SEC. 5 Special meetings may be 
called by the President and upon the 
request of any three members of the 
Board of Governors not including the 

SEC. 6 All members of the Society 
in any grade shall have the privilege of 
discussing technical material presented 
before the Society or its Sections. 

Bylaw VI 

SEC. 1 The President shall preside 
at all business meetings of the Society 
and shall perform the duties pertaining 
to that office. As such he shall be the 
chief executive of the Society, to whom 
all other officers shall report. 

SEC. 2 In the absence of the Presi- 
dent, the officer next in order as listed 
in Article IV of the Constitution shall 
preside at meetings and perform the 
duties of the President. 

SEC. 3 The five Vice-Presidents 
shall perform the duties separately enu- 
merated below for each office, or as de- 
fined by the President: 

(a) The Executive Vice-President 
shall represent the President in such 
geographical areas of the United States 
as shall be determined by the Board of 
Governors and shall be responsible for 
the supervision of the general affairs of 
the Society in such areas, as directed 
by the President of the Society. 
Should the President or Executive 
Vice-President remove his residence 

from the geographical area (Atlantic 
Coast or Pacific Coast) of the United 
States in which he resided at the time 
of his election, the office of Executive 
Vice-President shall immediately be- 
come vacant and a new Executive 
Vice-President elected by the Board of 
Governors for the unexpired portion of 
the term, the new Executive Vice- 
President to be a resident of that part 
of the United States from which the 
President or Executive Vice-President 
has just moved. 

(b) The Engineering Vice-President 
shall appoint all technical committees. 
He shall be responsible for the general 
initiation, supervision, and co-ordina- 
tion of the work in and among these 
committees. He may act as Chairman 
of any committee or otherwise be a 
member ex-officio. 

(c) The Editorial Vice-President 
shall be responsible for the publication 
of the Society's JOURNAL and all other 
technical publications. He shall pass 
upon the suitability of the material for 
publication, and shall cause material 
suitable for publication to be solicited 
as may be needed. He shall appoint a 
Papers Committee and an Editorial 
Committee. He may act as Chairman 
of any committee or otherwise be a 
member ex-officio. 

(d) The Financial Vice-President 
shall be responsible for the financial 
operations of the Society, and shall 
conduct them in accordance with bud- 
gets approved by the Board of Gover- 
nors. He shall study the costs of 
operation and the income possibilities 
to the end that the greatest service may 
be rendered to the members of the 
Society within the available funds. 
He shall submit proposed budgets to 
the Board. He shall appoint at his 
discretion a Ways and Means Com- 
mittee, a Membership Committee, a 
Commercial Advertising Committee, 




and such other committees within the 
scope of his work as may be needed. 
He may act as Chairman of any of 
these committees or otherwise be a 
member ex-officio. 

(e) The Convention Vice-President 
shall be responsible for the national 
conventions of the Society. He shall 
appoint a Convention Arrangements 
Committee, an Apparatus Exhibit 
Committee, and a Publicity Com- 
mittee. He may act as Chairman of 
any committee, or otherwise be a 
member ex-officio. 

SEC. 4 The Secretary shall keep a 
record of all meetings; he shall conduct 
the correspondence relating to his 
office, and shall have the care and cus- 
tody of records, and the seal of the 

SEC. 5 The Treasurer shall have 
charge of the funds of the Society and 
disburse them as and when authorized 
by the Financial Vice-President. He 
shall make an annual report, duly 
audited, to the Society, and a report 
at such other times as may be requested. 
He shall be bonded in an amount to be 
determined by the Board of Governors 
and his bond filed with the Secretary. 

SEC. 6 Each officer of the Society, 
upon the expiration of his term of office, 
shall transmit to his successor a memo- 
randum outlining the duties and poli- 
cies of his office. 

Bylaw VH 


SEC. 1 All officers and governors 
shall be elected to their respective 
offices by a majority of ballots cast by 
the Active, Fellow, and Honorary 
members in the following manner: 

Not less than three months prior to 
the annual fall convention, the Board of 
Governors shall nominate for each 
vacancy several suitable candidates. 

Nominations shall first be presented by 
a Nominating Committee appointed 
by the President, consisting of nine 
members, including a Chairman. The 
committee shall be made up of two Past- 
Presidents, three members of the 
Board of Governors not up for election, 
and four other Active, Fellow, or Hon- 
orary members, not currently officers 
or governors of the Society. Nomina- 
tions shall be made by three-quarters 
affirmative vote of the total Nominat- 
ing Committee. Such nominations 
shall be final unless any nominee is re- 
jected by a three-quarters vote of the 
Board of Governors present and voting. 

The Secretary shall then notify these 
candidates of their nomination. From 
the list of acceptances, not more than 
two names for each vacancy shall be 
selected by the Board of Governors 
and placed on a letter ballot. A blank 
space shall be provided on this letter 
ballot under each office, in which space 
the names of any Active, Fellow, or 
Honorary members other than those 
suggested by the Board o Governors 
may be voted for. The balloting shall 
then take place. 

The ballot shall be enclosed in a 
blank envelope which is enclosed in an 
outer envelope bearing the Secretary's 
address and a space for the member's 
name and address. One of these shall 
be mailed to each Active, Fellow, and 
Honorary member of the Society, not 
less than forty days in advance of the 
annual fall convention. 

The voter shall then indicate on the 
ballot one choice for each office, seal 
the ballot in the blank envelope, place 
this in the envelope addressed to the 
Secretary, sign his name and address on 
the latter, and mail it in accordance 
with the instructions printed on the 
ballot. No marks of any kind except 
those above prescribed shall be placed 
upon the ballots or envelopes. Voting 




shall close seven days before the open- 
ing session of the annual fall conven- 

The sealed envelope shall be de- 
livered by the Secretary to a Com- 
mittee of Tellers appointed by the Pres- 
ident at the annual fall convention. 
This committee shall then examine the 
return envelopes, open and count the 
ballots, and announce the results of the 

The newly elected officers and gover- 
nors of the general Society shall take 
office on January 1st following their 

Bylaw VIII 

SEC. 1 The annual dues shall be 
fifteen dollars ($15) for Fellows and 
, Active members, ten dollars ($10) for 
Associate members, and five dollars 
($5) for Student members, payable on 
or before January 1st of each year. 
Current or first year's dues for new 
members in any calendar year shall be 
at the full annual rate for those noti- 
fied of acceptance in the Society on or 
before June 30th; one half the annual 
rate for those notified of acceptance in 
the Society on or after July 1st. 

SEC. 2 (a) Transfer of membership 
to a higher grade may be made at any 
time. If the transfer is made on or 
before June 30th the annual dues of 
the higher grade is required. If the 
transfer is made on or after July 1st 
and the member's dues for the full year 
has been paid, one half of the annual 
dues of the higher grade is payable less 
one half the annual dues of the lower 

(b) No credit shall be given for an- 
nual dues in a membership transfer 
from a higher to a lower grade, and such 
transfers shall take place on January 
1st of each year. 

(c) The Board of Governors upon 
their own initiative and without a 
transfer application may elect, by the 
approval of at least three fourths of 
the Board, any Associate or Active 
member for transfer to any , higher 
grade of membership. 

SEC. 3 Annual dues shall be paid 
in advance. A new member who has 
not paid dues in advance shall be noti- 
fied of admittance but shall not receive 
the JOURNAL and is not in good stand- 
ing until initial dues are paid. All 
Honorary members, Fellows, and Ac- 
tive members in good standing, as de- 
fined in SECTION 5, may vote or other- 
wise participate in the meetings. 

SEC. 4 Members shall be considered 
delinquent whose annual dues for the 
year remain unpaid on February 1st. 
The first notice of delinquency shall be 
mailed February 1st. The second 
notice of delinquency shall be mailed, 
if necessary, on March 1st, and shall 
include a statement that the member's 
name will be removed from the mailing 
list for the JOURNAL and other publica- 
tions of the Society before the mailing 
of' the April issue of the JOURNAL. 
Members who are in arrears of dues on 
June 1st, after two notices of such de- 
linquency have been mailed to their 
last address of record, shall be notified 
their names have been removed from 
the mailing list and shall be warned 
unless remittance is received on or be- 
fore August 1st, their names shall be 
submitted to the Board of Governors 
for action at the next meeting. Back 
issues of the JOURNAL shall be sent, if 
available, to members whose dues have 
been paid prior to August 1st. 

SEC. 5 (a) Members whose dues re- 
main unpaid on October 1st may be 
dropped from the rolls of the Society by 
majority vote and action of the Board, 
or the Board may take such action as it 
sees fit. 




(b) Anyone who has been dropped 
from the rolls of the Society for non- 
payment of dues shall, in the event of 
his application for reinstatement, be 
considered as a new member. 

(c) Any member may be suspended 
or expelled for cause by a majority vote 
of the entire Board of Governors; 
provided he shall be given notice and a 
copy in writing of the charges pre- 
ferred against him, and shall be af- 
forded opportunity to be heard ten 
days prior to such action. 

SEC. 6 The provisions of SECTIONS 
1 to 4, inclusive, of this Bylaw VIII 
given above may be modified or re- 
scinded by action of the Board of 

Bylaw IX 

SEC. 1 The emblem of the Society 
shall be a facsimile of a four-hole film 
reel with the letter S in the upper cen- 
ter opening, and the letters M, P, and 
E, in the three lower openings, re- 
spectively. The Society's emblem 
may be worn by members only. 

Bylaw X 

SEC. 1 Papers read at meetings or 
submitted at other times, and all ma- 
terial of general interest shall be sub- 
mitted to the Editorial Board, and 
those deemed worthy of permanent 
record shall be printed in the JOURNAL. 
A copy of each issue shall be mailed to 
each member in good standing to his 
last address of record. Extra copies 
of the JOURNAL shall be printed for 
general distribution and may be ob- 
tained from the General Office on pay- 
ment of a fee fixed by the Board of 

Bylaw XI 
SBC. 1 Sections of the Society may 

be authorized in any state or locality 
where the Active, Fellow, and Honor- 
ary membership exceeds 20. The geo- 
graphic boundaries of each Section 
shall be determined by the Board of 

Upon written petition, signed by 20 
or more Active members, Fellows, and 
Honorary members, for the authoriza- 
tion of a Section of the Society, the 
Board of Governors may grant such 

SEC. 2 All members of the Society 
of Motion Picture Engineers in good 
standing residing in that portion of 
any country set apart by the Board of 
Governors tributary to any local Sec- 
tion shall be eligible for membership 
in that Section, and when so enrolled 
they shall be entitled to all privileges 
that such local Section may, under the 
General Society's Constitution and 
Bylaws, provide. 

Any member of the Society in good 
standing shall be eligible for nonresi- 
dent affiliated membership of any Sec- 
tion under conditions and obligations 
prescribed for the Section. An affili- 
ated member shall receive all notices 
and publications of the Section but he 
shall not be entitled to vote at sectional 

SEC. 3 Should the enrolled Active, 
Fellow, and Honorary membership of a 
Section fall below 20, or should the 
technical quality of the presented 
papers fall below an acceptable level, 
or the average attendance at meetings 
not warrant the expense of maintaining 
the organization, the Board of Gover- 
nors may cancel its authorization. 


.SEC. 4 The officers of each Section 
shall be a Chairman and a Secretary- 
Treasurer. The Section chairmen 




shall automatically become members 
of the Board of Governors of the 
General Society, and continue in such 
positions for the duration of their terms 
as chairmen of the local Sections. 
Each Section officer shall hold office for 
one year, or until his successor is 

SEC. 5 The Board of Managers 
shall consist of the Section Chairman, 
the Section Past-Chairman, the Section 
Secretary-Treasurer, and six Active, 
Fellow, or Honorary members. Each 
manager of a Section shall hold office 
for two years, or until his successor is 

SEC. 6 The officers and managers 
of a Section shall be Active, Fellow, or 
Honorary members of the General 
Society. All officers and managers 
shall be elected to their respective 
offices by a majority of ballots cast by 
the Active, Fellow, and Honorary 
members residing in the geographical 
area covered by the Section. 

Not less than three months prior to 
the annual fall convention of the So- 
ciety, nominations shall be presented to 
the Board of Managers of the Section 
by a Nominating Committee ap- 
pointed by the Chairman of the Sec- 
tion, consisting of seven members, in- 
cluding a chairman. The Committee 
shall be composed of the present Chair- 
man, the Past-Chairman, two other 
members of the Board of Managers not 
up for election, and three other Active, 
Fellow, or Honorary members of the 
Section not currently officers or man- 
agers of the Section. Nominations 
shall be made by a three-quarters af- 
firmative vote of the total Nominating 
Committee. Such nominations shall 
be final, unless any nominee is rejected 

by a three-quarters vote of the Board of 
Managers, and in the event of such re- 
jection the Board of Managers will 
make its own nomination. 

The Chairman of the Section shall 
then notify these candidates of their 
nomination. From the list of accept- 
ances, not more than two names for 
each, vacancy shall be selected by the 
Board of Managers and placed on a 
letter ballot. A blank space shall be 
provided on this letter ballot under 
each office, in which space the names 
of any Active, Fellow, or Honorary 
members other than those suggested 
by the Board of Managers may be 
voted for. The balloting shall then 
take place. 

The ballot shall be enclosed in a 
blank envelope which is enclosed in an 
outer envelope bearing the local Secre- 
tary-Treasurer's address and a space 
for the member's name and address. 
One of these shall be mailed to each 
Active, Fellow, and Honorary member 
of the Society residing in the geographi- 
cal area covered by the Section, not 
less than forty days in advance of the 
annual fall convention. 

The voter shall then indicate on the 
ballot one choice for each office, seal 
the ballot in the blank envelope, place 
this in the envelope addressed to the 
Secretary-Treasurer, sign his name and 
.address on the latter, and mail it in 
accordance with the instructions 
printed on the ballot. No marks of 
any kind except those above pre- 
scribed shall be placed upon the ballots 
or envelopes. Voting shall close seven 
days before the opening session of the 
annual fall convention. 

The sealed envelopes shall be de- 
livered by the Secretary-Treasurer to 
his Board of Managers at a duly called 
meeting. The Board of Managers 
shall then examine the return enve- 
lopes, open and count the ballots, and 




announce the results of the election. 
The newly elected officers and man- 
agers shall take office on January 1st 
following their election. 

SEC. 7 The business of a Section 
shall be conducted by the Board of 

SEC.' 8 (a) As early as possible in 
the fiscal year, the Secretary-Treasurer 
of each Section shall submit to the 
Board of Governors of the Society a 
budget of expenses for the year. 

(b)The Treasurer of the General 
Society may deposit with each Section 
Secretary-Treasurer a sum of money, 
the amount to be fixed by the Board of 
Governors, for current expenses. 

(c) The Secretary-Treasurer of each 
Section shall send to the Treasurer of 
the General Society, quarterly or on 
demand, an itemized account of all 
expenditures incurred during the pre- 
ceding interval. 

(d) Expenses other than those enu- 
merated in the budget, as approved by 
the Board of Governors of the General 
Society, shall not be payable from the 
general funds of the Society without 
express permission from the Board of 

(e) A Section Board of Managers 
shall defray all expenses of the Section 
not provided for by the Board of 
Governors, from funds raised locally by 
donation, or fixed annual dues, or by 

(f ) The Secretary of the General 
Society shall, unless otherwise ar- 
ranged, supply to each Section all 
stationery and printing necessary for 
the conduct of its business. 

SEC. 9 The regular meetings of a 
Section shall be held in such places and 

at such hours as the Board of Managers 
may designate. 

The Secretary-Treasurer of each 
Section shall forward to the Secretary 
of the General Society, not later than 
five days after a meeting of a Section, 
a statement of the attendance and of 
the business transacted. 


.SEC. 10 Papers shall be approved 
by the Section's Papers Committee 
previously to their being presented be- 
fore a Section. Manuscripts of papers 
presented before a Section, together 
with a report of the discussions and the 
proceedings of the Section meetings, 
shall be forwarded promptly by the 
Section Secretary-Treasurer to the 
Secretary of the General Society. 
Such material may, at the discretion of 
the Board of Editors of the General 
Society, be printed in the Society's 

SEC. 11 Sections shall abide by the 
Constitution and Bylaws of the Society 
and conform to the regulations of the 
Board of Governors. The conduct of 
Sections shall always be in conformity 
with the general policy of the Society 
as fixed by the Board of Governors. 

Bylaw XII 

SEC. 1 These Bylaws may be 
amended at any regular meeting of the 
Society by the affirmative vote of two 
thirds of the members present at a 
meeting who are eligible to vote there- 
on, a quorum being present, either on 
the recommendation of the Board of 
Governors or by a recommendation to 
the Board of Governors signed by any 
ten members of Active or higher grade, 
provided that the proposed amend- 
ment or amendments shall have been 




published in the JOURNAL of the So- 
ciety, in the issue next preceding the 
date of the stated business meeting 
of the Society at which the amendment 
or amendments are to be acted upon. 

SEC. 2 In the event that no quorum 
of the voting members is present at the 
time of the meeting referred to in 
SECTION 1, the amendment or amend- 
ments shall be referred for action to the 
Board of Governors. The proposed 
amendment or amendments then be- 
come a part of the Bylaws upon re- 
ceiving the affirmative vote of three 
quarters of the Board of Governors. 

Bylaw XIII 

SEC. 1 Student Chapters of the 
Society may be authorized in any col- 
lege, university, or technical institute 
of collegiate standing. 

Upon written petition, signed by 
twelve or more Society members, or 
applicants for Society membership, 
and the Faculty Adviser, for the au- 
thorization of a Student Chapter, the 
Board of Governors may grant such 

SEC. 2 All members of the Society 
of Motion Picture Engineers in good 
standing who are attending the de- 
signated educational institution shall 
be eligible fqr membership in the 
Student Chapter, and when so enrolled 
they shall be entitled to all privileges 
that such Student Chapter may, under 
the General Society's Constitution and 
Bylaws, provide. 

SEC. 3 Should the membership of 
the Student Chapter fall below ten, or 
should the technical quality of the pre- 
sented papers fall below an acceptable 
level, or the average attendance at 
meetings not warrant the expense of 

maintaining the organization, the 
Board of Governors may cancel its 

SEC. 4 The officers of each Student 
Chapter shall be a Chairman and a 
Secretary-Treasurer. Each Chapter 
officer shall hold office for one year, or 
until his successor is chosen. Officers 
shall be chosen in May to take office at 
the beginning of the following school 
year. The procedure for holding elec- 
tions shall be prescribed in Adminis- 
trative Practices. 


SEC. 5 A member of the faculty of 
the same educational institution shall 
be designated by the Board of Gover- 
nors as Faculty Adviser. It shall be 
his duty to advise the officers on the 
conduct of the Chapter and to approve 
all reports to the Secretary and the 
Treasurer of the Society. 

SEC. 6 The Treasurer of the 
General Society may deposit with each 
Chapter Secretary-Treasurer a sum of 
money, the amount to be fixed by the 
Board of Governors. The Secretary- 
Treasurer shall send to the Treasurer 
of the General Society at the end of 
each school year an itemized account 
of all expenditures incurred during 
that period. 

SEC. 7 The Chapter shall hold at 
least four meetings per year. The 
Secretary-Treasurer shall forward to 
the Secretary of the General Society at 
the end of each school year a report of 
the meetings for that year, giving the 
subject, speaker, and approximate 
attendance for each meeting. 


In accordance with the provisions of Administrative Practices of the Society, 
the regulations for procedure in granting the Journal Award, the Progress Medal 
Award, and the Samuel L. Warner Memorial Award, a list of the names of previous 
recipients, and the reasons therefor, are published annually in the JOURNAL as 


The Journal Award Committee shall consist of five Fellows or Active members 
of the Society, appointed by the President and confirmed by the Board of Gover- 
nors. The Chairman of the Committee shall be designated by the President. 

At the fall convention of the Society a Journal Award Certificate shall be pre- 
sented to the author or to each of the authors of the most outstanding paper 
originally published in the JOURNAL of the Society during the preceding calendar 

Other papers published in the JOURNAL of the Society may be cited for Honor- 
able Mention at the option of the Committee, but in any case should not exceed 
five in number. 

The Journal Award shall be made on the basis of the following qualifications: 

(1) The paper must deal with some technical phase of motion picture engineer- 

(2) No paper given in connection with thfe receipt of any other Award of the 
Society shall be eligible. 

(3) In judging of the merits of the paper, three qualities shall be considered, 
with the weights here indicated: 

(a) Technical merit and importance of material 45 per cent. 

b) Originality and breadth of interest 35 per cent. 

c) Excellence of presentation of the material 20 per cent. 

A majority vote of the entire Committee shall be required for the election to the 
Award. Absent members may vote in writing. 

The report of the Committee shall be presented to the Board of Governors at 
their July meeting for ratification. 

These regulations, a list of the names of those who have previously received the 
Journal Award, the year of each Award, and the titles of the papers shall be pub- 
lished annually in the 1 April issue of the JOURNAL of the Society. In addition, the 
list of papers selected for Honorable Mention shall be published in the JOURNAL of 
the Society during the year current with the Award. 

The Awards in previous years have been as follows: 

1934 P. A. Snell, for his paper entitled "An Introduction to the Experi- 
mental Study of Visual Fatigue." (Published May, 1933.) 

1935 L. A. Jones and J. H. Webb, for their paper entitled "Reciprocity 
Law Failure in Photographic Exposure." (Published September, 1934.) 

1936 E. W. Kellogg, for his paper entitled "A Comparison of Variable- 
Density and Variable- Width Systems." (Published September, 1935.) 

1937 D. B. Judd, for his paper entitled "Color Blindness and Anomalies of 
Vision." (Published June, 1936.) 



1938 K. S. Gibson, for his paper entitled "The Analysis and Specification of 
Color." (Published April, 1937.) 

1939 H. T. Kalmus, for his paper entitled "Technicolor Adventures in 
Cinemaland." (Published December, 1938.) 

1940 R. R. McNath, for his paper entitled "The Surface of the Nearest 
Star." (Published March, 1939.) 

1941 J. G. Frayne and Vincent Pagliarulo, for their paper entitled "The 
Effects of Ultraviolet Light on Variable-Density Recording and Printing." 
(Published June, 1940.) 

1942 W. J. Albersheim and Donald MacKenzie, for their paper entitled 
"Analysis of Sound-Film Drives." (Published July, 1941.) 

1943 R. R. Scoville and W. L. Bell, for their paper entitled "Design and 
Use of Noise-Reduction Bias Systems." (Published February, 1942; Award 
made April, 1944.) 

1944 J. I. Crabtree, G. T. Eaton, and M. E. Muehler, for their paper en- 
titled "Removal of Hypo and Silver Salts from Photographfc Materials as 
Affected by the Composition of the Processing Solutions." (Published July. 

1945 C. J. Kunz, H. E. Goldberg, and C. E. Ives, for their paper entitled 
"Improvement in Illumination Efficiency of Motion Picture Printers/' (Pub- 
lished May, 1944.) 

1946 R. H. Talbot, for his paper entitled "The Projection Life of Film." 
(Published August, 1945.) 

1947 Albert Rose, for his paper entitled "A Unified Approach to the Per- 
formance of Photographic Film, Television Pickup Tubes, and the Human 
Eye." (Published October, 1946.) 

The present Chairman of the Journal Award Committee is J. I. Crabtree. 


The Progress Medal Award Committee shall consist of five Fellows or Active 
members of the Society, appointed by the President and confirmed by the Board 
of Governors. The Chairman of the Committee shall be designated by the 

The Progress Medal may be awarded each year to an individual in recognition 
of any invention, research, or development which, in the opinion of the Com- 
mittee, shall have resulted in a significant advance in the development of motion 
picture technology. 

Any member of the Society may recommend persons deemed worthy of the 
Award. The recommendation in each case shall be in writing and in detail as to 
the accomplishments which are thought to justify consideration. The recom- 
mendation shall be seconded in writing by any two Fellows or Active members 
of the Society, who shall set forth their knowledge of the accomplishments of the 
candidate which, in their opinion, justify consideration. 

A majority vote of the entire Committee shall be required to constitute an 
Award of the Progress Medal. Absent members may vote in writing. 

The report of the Committee shall be presented to the Board of Governors 
at their July meeting for ratification. 

The recipient of the Progress Medal shall be asked to present a photograph of 
himself to the Society and, at the discretion of the Committee, may be asked to 
prepare a paper for publication in the JOURNAL of the Society. 

These regulations, a list of the names of those who have previously received 

410 AWARDS April 

the Medal, the year of each Award, and a statement of the reason for the Award 
shall be published annually in the April issue of the JOURNAL of the Society. 
Previous Awards have been as follows: 

The 1935 Award was made to E. C. Werite, for his work in the field of sound 
recording and reproduction. (Citation published December, 1935.) 

The 1936 Award was made to C. E. K. Mees, for his work in photography. 
(Citation published December, 1936.) 

The 1937 Award was made to E. W. Kellogg, for his work in the field of sound 
reproduction. (Citation published December, 1937.) 

The 1938 Award was made to H. T. Kalmus, for his work in developing color 
motion pictures. (Citation published December, 1938.) 

The 1939 Award was made to L. A. Jones, for his scientific researches in the 
field of photography. (Citation published December, 1939.) 

The 1940 Award was made to Walt Disney, for his contributions to motion 
picture photography and sound recording of feature and short cartoon films. 
(Citation published December, 1940.) 

The 1941 Award was made to G. L. Dimmick, for his development activities 
in motion picture sound recording. (Citation published December, 1941.) 

No Awards were made in 1942 and 1943. 

The 1944 Award was made to J. G. Capstaff, for his research and develop- 
ment of films and apparatus used in amateur cinematography. (Citation pub- 
lished January, 1945.) 

No Awards were made in 1945 and 1946. 

The 1947 Award was made to J. G. Frayne for his technical achievements and 
the documenting of his work in addition to his contributions to the field of edu- 
cation and his inspiration to his fellow engineers. (Citation published January, 

The present Chairman of the Progress Medal Award Committee is F. E. Carl- 



Each year the President shall appoint a Samuel L. Warner Memorial Award 
Committee consisting of a chairman and four members. The chairman and 
committee members must be Active Members or Fellows of the Society. In con- 
sidering candidates for the Award, the committee shall give preference to inven- 
tions or developments occurring in the last five years. Preference should also be 




given to the invention or development likely to have the widest and most bene- 
ficial effect on the quality of the reproduced sound and picture. A description of 
the method or apparatus must be available for publication in sufficient detail so 
that it may be followed by anyone skilled in the art. Since the Award is made to 
an individual, a development in which a group participates should be considered 
only if one person has contributed the basic idea and also has contributed sub- 
stantially to the practical working out of the idea. If, in any year, the committee 
does not consider any recent development to be more than the logical working out 
of details along well-known lines, no recommendation for the Award shall be made. 
The recommendation of the committee shall be presented to the Board of Gover- 
nors at the July meeting. 

The purpose of this Award is to encourage the development of new and im- 
proved methods or apparatus designed for sound-on-film motion pictures, in- 
cluding any step in the process. 

Any person, whether or not a member of the Society of Motion Picture En- 
gineers, is eligible to receive the Award. 

The Award shall consist of a gold medal suitably engraved for each recipient. 
It shall be presented at the Fall Convention of the Society, together with a bronze 

These regulations, a list of those who previously have received the Award, and 
a statement of the reason for the Award shall be published annually in the April 
issue of the JOURNAL of the Society. 

The 1947 Award was made to J. A. Maurer, for his outstanding contributions 
to the field of high-quality 16-mm sound recording and reproduction, film proc- 
essing, development of 16-mm sound test films, and for his inspired leadership 
in industry standardization. 

The present Chairman of the Samuel L. Warner Memorial Award Committee 
is P. E. Brigandi. 


Committees of the Society 
Committee personnel will be published in the May, 1948, issue of the Journal. 

Society of Motion Picture Engineers 


Changes for Period January December 31, 1947 

Hon. Sust. Pel. Act. Asso. Stu. Total 

Membership, Jan. 1, 1947 6 64 154 561 1588 59 2432 

New Members 3 107 238 88 435 

Reinstatements 49 13 

6 67 154 672 1835 147 2880 

Less: Resignations 1 6 35 4 46 

Deaths .-2 -3 -3 -8 

Suspended -24* -25 -109 -17 -175 


43 151 638 1688 

126 2651 

Changes in Grade: 

Active to Fellow 

14 -14 

Associate to Active 

54 -54 

Active to Associate 

-3 3 

Associate to Student 



Membership, Dec. 31, 1947 6 

43 165 675 1636 

127 2651 


Subscriptions, Jan. 1, 1947 


New subscriptions and renewals, 

Jan.-Dec., 1947 




Less : Expirations 


Subscriptions, Dec. 31, 1947 


* Grades: Honorary, Sustaining, Fellow, Active, Associate, and kStudent. 


Society of Motion Picture Engineers 


January 1- December 31, 1947 
Members' Equity, January 1, 1947: 


Receipts, Jan.-Dec. 1947: 
Membership dues $28,115.42 

Sustaining Memberships 20,575.00 ' 

Publications 12,381.66 

Test Films 25,923.31 

Other (Interest, etc.) 1,087.50 

Total Receipts $88,082.89 , 

Disbursements, Jan. -Dec. 1947: 

General Office $41,573.15 

Publications 17,700.62 

Test Films 12,758.07 

Dues and Fees to Other Or- 
ganizations 485.00 
Sections 1,274.71 
Committee Activities 1,714.88 
Other (Conventions, Awards, 

etc.) 947.95 

Total Disbursements 76,454.38 

Excess Receipts Over Disburse- 
ments, 1947: $11,628.51 

. Accrued Interest on Savings 

Accounts 157.03 

Members' Equity, December 31, 1947 $90,759.32 

Respectfully submitted, 
E. A. BERTRAM, Treasurer 

The cash records of the Treasurer were audited for the year 
ended December 31, 1947, by Sparrow, Waymouth and Company, 
certified public accountants, New York, and are in conformity 
with the above report. 

Financial Vice- President 

Society Announcements 

Progress Medal Award 

The SMPE Progress Medal Award is presented to an individual in recognition 
of his technical contributions to the motion picture industry. This is an annual 
award; however, it need not be presented in any given'year if the Progress Medal 
Award Committee feels that there is no qualified candidate. Candidates may be 
proposed by any member of the Society as outlined in the formal committee pro- 
cedure on page 409 of this issue of the Journal. 

Proposals for consideration by the committee may be addressed to any member 
of the committee which is listed below, but must be received prior to May 15, 

H. B. Braun, Radio City Music Hall, Rockefeller Center, N. Y. 20, N. Y. 
II. M. Corbin, Eastman Kodak. Company. Rochester, N. Y. 
W. C. Miller, Metro-Goldwyn-Mayer, Culver City, Calif. 
F. E. Carlson, General Electric Co., Nela Park, Cleveland 12, Ohio. 
John W. Boyle, 139V 2 Doheny Dr., Los Angeles 36, Calif. 

The Progress Medal was inaugurated during the term of office of President J. I. 
Crabtree but much credit is due Mr. G. E. Matthews, the then chairman of the 
Historical Committee, for his efforts in obtaining an outstanding design. Sketches 
for the proposed medal were submitted by some of the better-known artists in 
New York City but these were mostly conventional featuring the laurel wreath. 
Fortunately Mr. Alexander Murray, a co-worker with Messrs. Crabtree and 
Matthews in the Research Laboratories of the Eastman Kodak Company, became 
interested in the problem and submitted a unique design incorporating many 
symbols peculiar to the photographic and motion picture art and donated his work 
to the Society. A picture of the medal is shown on page 410. 

The design 'was approved unanimously by the Board of Governors, precision 
dies made by the Metal Arts Company, Rochester, N. Y., and the first gold medal 
struck in the year 1935 which, on recommendation of the Progress Award Com- 
mittee, was awarded to Dr. E. C. Wente of the Bell Telephone Laboratories. 

The design of the medal is uniquely symbolic of progress in the cinema. 
On the obverse side, the center is a replica of the official emblem of the Society. 
Above and around the emblem are embossed the words "For Progress," and below 
are two laurel branches, Grecian symbols of achievement. A reproduction of 
film perforations forms a decorative motif surrounding the central portion of the 
design. Eleven concave panels fill the remaining area extending to the outer edge 
of the face, upon 6ach of which the form of a bird in flight is embossed. Various 
movements of the flight are depicted, reproducing the work of E. Marey, a French 
scientist who, in 1886, designed a "photographic gun," using circular glass plates, 
for analyzing the movements of living things. Although it was not Marey's 
intention to reproduce motion, his plates embodied the essential elements of the 
motion picture and the representation of them is therefore symbolic of the early 
development of motion pictures. 

On the reverse side, the central portion consists of a series of horizontal oblong 
panels arranged in a partial pyramidal form and bearing the embossed inscription 
"Awarded to (Name of Medalist) for Outstanding Achievement in Motion Picture 


Technology." Crystals of silver bromide, the light-sensitive salt used in most 
photographic emulsions, are reproduced in two of the panels. Below the inscrip- 
tion is engraved the year of the award. Above it is a small rectangular panel 
upon which is engraved a sensitometric curve, representing the classical researches 
of Hurter and Driffield, who laid down much of the fundamental theory regarding 
numerical specification of photographic emulsion characteristics. Sine waves, 
symbolic of sound and light, are embossed upon two curved panels to the left and 
right of the central pyramid. In a slightly inclined panel surrounding almost the 
entire outer edge, the name of the Society appears in embossed letters. 

Current Literature 

IN RECENT ISSUES of the Philips Technical Review, there have appeared 
articles which should prove of great interest to the motion picture engi- 
neer. The summary of one of these papers is given below. THE EDITOR 



The resolving power of a film made by the usual photographic methods is 
limited by the circle of diffusion formed by the grains of the film. Consequently 
in order to get sharp pictures on the projection screen the images on the film must 
be of a certain minimum size. If the film carries a sound track and the speed of 
the projected film is fixed, then, in spite of a so-called cancellation method being 
applied when recording and copying, this limited resolving power results in a loss 
in the amplitude of high frequencies. In order to counteract the circle of diffusion 
it is desirable that the film should have a high gamma, of say 4 or 5. For picture 
reproduction, however, Goldberg's rule prescribes a gamma in the neighborhood of 
1 or 2. The compromise that has to be reached when a picture film and a sound 
track have to be copied on a single film by the usual methods makes its influence 
felt throughout the whole of the present-day technique of cinematography. 

A much simpler and less expensive solution of the problem of copying sound 
films is offered by a new method of photographic reproduction that was developed 
in the Philips laboratories during the war. This method is based on the use of a 
diazonium compound combined with a mercury salt. The most striking features 
of this method are the extremely high resolving power (1000 lines per millimeter) 
and the locally variable gamma (between, e. g., 1 and 8). A more detailed 
description of this method and its possibilities of application will be given in 
another article to be published in this journal shortly. (FromVolume 9, Number 3) 


63rd Semiannual Convention 


Santa Monica Ambassador Hotel 
Santa Monica, California 

May 17-21, 1948 

Monday, May 17 

1) : 30 A.M. Registration, Sixth Floor, Santa Monica Ambassador Hotel 

Advance Sale of Luncheon and Banquet Tickets 

1 1 :00 A.M. Business Session, Magnolia Room, Santa Monica Ambassador Hotel 
Introduction of Society Officers 
Report of the President 
Report of the Convention Vice-President 

Standards Committee Report, F. T. Bowditch, Research Labora- 
tories, National Carbon Company, Cleveland, Ohio 
Report of Committee on High-Speed Photography, A. P. Neyhart, 

Douglas Aircraft Company, Santa Monica, California 
12:30 P.M. Luncheon, Ocean Room, Del Mar Beach Club, for members and 

guests. Mr. Loren Ryder, president of the Society, will preside. 
2:00 P.M. Technical Session, Magnolia Room 

Session will open with a 35-mm motion picture short 

"Tentative Standards for Noise and Distortion Measurements," by 

E. W. Kellogg, RCA Victor Division, Radio Corporation of 

America, Indianapolis, Indiana 
"Variable-Area Recording with the Light Valve," by J. G. Frayne, 

Western Electric Company, Hollywood, California 
"A Light-Valve Variable-Area Modulator," by L. B. Browder, 

Western Electric Company, Hollywood, California 
"A 'Silent' Playback and Public-Address System," by B. H. Denney % 

and Robert J. Carr, Paramount Pictures, Inc., Hollywood, 

"Volume Compressors /or Sound Recording," by W. K. Grimwood, 

Research Laboratories, Eastman Kodak Company, Rochester, 

New York 
"A Single-Element Unidirectional ]\licrophone," by Harry F. Olson, 

and John Preston, Research Laboratories, Radio Corporation of 

America, Princeton, New Jersey 
8:00 P.M. Technical Session, Magnolia Room 

Session will open with a 35-mm motion picture short 

"Flicker in Motion Pictures; Further Studies," by L. D. Griguon, 

20th Century-Fox Film Corporation, Beverly Hills, California 
"Audio-Visual Materials Prospects and Needs," by Donald C. 

Doane, Director, Audio-Visual Laboratory, University of South- 
ern California, Los Angeles, California 



Monday, May 17 (Continued) 

8:00 P.M. Technical Session (Continued) 

"The Film Collection Program in the Academy of Motion Picture 
Arts and Sciences," by H. L. Walls, Academy of Motion Picture 
Arts and Sciences, Los Angeles, California 

"Problems of Locating Theater Sites," by E. G. Faludi, City Plan- 
ning Consultant, Toronto, Ontario, Canada 

"Technical Aspects of 16-Mm Feature Motion Picture Production," 
by R. Adams, Telefilm, Inc., Hollywood, California 

"Animation/* by K. Dodal, Irena Film Studios, New York, New 

Tuesday, May 18 

9:30 A.M. Registration, Sixth Floor, Santa Monica Ambassador Hotel 

Advance Sale of Banquet Tickets 
10:00 A.M. Technical Session, Magnolia Room 

Session will open with a 35-mm motion picture short 

"The Present State of the Art in Evaluating Loudspeaker Perform- 
ance," by J. K. Hilliard, Altec Lansing Corporation, Los Angeles, 

"An Experiment in Stereophonic Sound," by L. D. Grignon, 20th 
Century-Fox Film Corporation, Beverly Hills, California 

"Double- Width Optical System for Recording," by L. T. Sachtleben, 
RCA Victor Division, Radio Corporation of America, Camden, 
New Jersey 

"The Technique of Reducing Sound Distortion by Compromise Ad- 
justments and Anticipation of Noise Reduction," by R. A. Dupy, 
Metro-Goldwyn-Mayer Studios, Culver City, California 

"Progress Report on the Standardization of Home Phonograph Re- 
cording and Reproduction," J. K. Hilliard, Altec Lansing Corpora- 
tion, Los Angeles, California 
2:00 P.M. Technical Session, Magnolia Room 

Session will open with a 35-mm motion picture short 

"Magnetic-Sound Recording for the Motion Picture Technician," 
by D. O'Dea, RCA Victor Division, Radio Corporation of Amer- 
ica, Hollywood, California 

"Magnetic-Recording Heads," by G. L. Dimmick, Radio Corpora- 
tion of America, Indianapolis, Indiana 

"Film-Drive System for a Combination Photographic and Magnetic 
Sound Recorder," by J. L. Pettus, RCA Victor Division, Radio 
Corporation of America, Hollywood, California 

"Some Distinctive Properties of Magnetic Recording Media," by 
Robert Herr, Minnesota Mining and Manufacturing Co., St. 
Paul, Minnesota 

"Magnetic Recording as a Solution to Certain Sound Production 
Problems," by J. T. Mullin, W. A. Palmer and Company, San 
Francisco, California 


Tuesday, May 18 (Continued) 
2: 00 P.M. Technical Session (continued) 

"Stereophonic Magnetic Recording," by Marvin Camras, Armour 

Research Foundation, Chicago, Illinois 
"Magnetic Sound for 8-Mm Motion Pictures," by H. A. Leedy, 

Armour Research Foundation, Chicago, Illinois 
2:00 P.M. Technical Session, Rouge Room, Fourth Floor, Santa Monica 

Ambassador Hotel 
New Equipment Items. The equipment or techniques described will 

be on display 
"An Improved Camera .Crane," by Andre Grot, Motion Picture 

Research Council, Hollywood, California 

"Soundproofing Generators," by Earl Miller, RKO Studios, Holly- 
wood, California 

"An Improved Artificial Snow," by M. Martin, RKO Studios, Holly- 
wood, California 

"Make-Believe Bullet Holes," by M. Martin, RKO Studios, Holly- 
wood, California 
"A Magnetic Device for Cuing Film," by James A. Larsen, Academy 

Films, Hollywood, California 
"An Improved 35-Mm Synchronous Counter," by Robert A. Sater 

and J. W. Kaylor, Cinecolor Corporation, Burbank, California 
"1000-Foot Bipack Magazine and Adapter," by W. R. Holm and 

J. W. Kaylor, Cinecolor Corporation, Burbank, California 
"Splicing Machine," by E. J. Denison, Unite'd Artists Productions, 

Hollywood, California 
"Depth jof Field Indicator," by C. R. Daily, Paramount Pictures, 

Inc., Hollywood, California 
"A Time-Interval Marking Device for Motion Picture Cameras," 

by C. N. Edwards, U. S. NavaMPhotographic Center, Anacostia, 

D. C. 
8:00 P.M. Technical Session, Magnolia Room 

Session will open with a 35-mm motion picture short 
"Sensitometric Aspects of Television Monitor-Tube Photography," 

by F. G. Albin, RCA Victor Division, Radio Corporation of 

America, Hollywood, California 
"16-Mm Film as a Medium for Television Program Material," by 

J. A. Maurer, J. A. Maurer, Inc., Long Island City, New York 
"Programming Aspect of Television Production," by R. A. Monfort, 

Times-Mirror Company, Los Angeles, California 
"Films for Television," by Jerry Fairbanks, Jerry Fairbanks, Inc., 

Hollywood, California 
"Television Transmission Facilities to Be Provided by the Telephone 

Companies," by E. H. Schreiber, Pacific Telephone and Telegraph 

Company, Los Angeles, California 
Demonstration of Direct Pickup Large-Screen Television 


Wednesday, May 19 

9 : 30 A.M. Registration, Sixth Floor, Ambassador Hotel 

Advance Sale of Banquet Tickets 
10: 30 A.M. Demonstration by Thorobred Photo Service, Inc., at Hollywood 

Park Race Track, by arrangement with Colonel Nathan Levinson 

Warner Bros. Pictures, Inc. 

This demonstration of the methods used in horserace photography 
is limited to registrants and wives. Cab service will be available 
from the Santa Monica Ambassador Hotel to Hollywood Park. A 
regular afternoon racing session begins at 1 : 00 P.M. Members are 
welcome to spend the afternoon at the track. 


NOTE : Registration headquarters will be open on this afternoon 
until 3: 00 P.M. for those desiring Banquet tickets and making table 
7: 15 P.M. Cocktail Hour, for holders of Banquet tickets, Rouge Room, Santa 

Monica Ambassador Hotel 

8:30 P.M. 63rd Semiannual Banquet (dress optional), Magnolia Room, Santa 
Monica Ambassador Hotel. Entertainment and dancing 

Thursday, May 20 

2:00 P.M. Technical Session, Magnolia Room 

Joint meeting with Inter-Society Color Council 
Session will open with a 35-mm motion picture short (in color) 
"Characteristics of Light Sources/' by Norman Macbeth, Consult- 
ing Engineer, New York, New York 

"Color Phenomena," by I. A. Balinkin, University of Cincinnati 
"Basic Principles of Color Systems," by Carl E. Foss, Inter-Society 

Color Council 
"Some Systems in Color Preference," by J. P. Guilford, Beverly 

Hills, California 
2:00 P.M. Technical Session, Rouge Room 

New Equipment Items. . The equipment or techniques described will 

be on display 
"New Microphone," by Howard Souther, Stephens Manufacturing 

Company, Los Angeles, California 
"New Speaker for Separate Two- Way Systems," by Howard Souther, 

Stephens Manufacturing Company, Los Angeles, California 
"An Improved 35-Mm to 16-Mm Optical Reduction Sound Printer," 

by J. L. Pettus, RCA Victor Division, Radio Corporation of 

America, Hollywood, California 
"16-Mm Film Phonograph," by C. E. Kittle, RCA Victor Division, 

Radio Corporation of America, Hollywood, California 
"New Location Trucks," by Staff Member, RCA Victor Division, 

Radio Corporation of America, Hollywood, California 


Thursday, May 20 (continued) 
2: 00 P.M. Technical Session (continued) 

"A New Film Gate," by C. Wagner, Chris Wagner Company, Los 

Angeles, California 

"Notch Cued Sound-Track Control," by J. D. Stack, 20th Century- 
Fox Film Corporation, Beverly Hills, California 
"Review-Room Footage Counter," by J. D. Stack and R. Quan- 

strom, 20th Century-Fox Film Corporation, Beverly Hills, 

"A Graphic Equalizer," by Fred R. Wilson, Samuel Goldwyn 

Studios, Hollywood, California 
8:00 P.M. Technical Session, Academy Award Theatre, 9038 Melrose Ave., 

Los Angeles, California 

Joint meeting with Inter-Society Color Council 
Session will open with a 35-mm motion picture short (in color) 
Demonstration Lecture: "An Introduction to Color," by Ralph M. 

Evans, Eastman Kodak Company, Rochester, New York 

Friday, May 21 

2:00 P.M. Technical Session, Magnolia Room 

Session will open with a 35-mm motion picture short 

"An Integral Disk Recording and 8-Mm Motion Picture Reel for 
Synchronized Sound Motion Pictures," by P. Goldstone and R. 
Like, Phonovision Corporation, Hollywood, California 

"Specifications for Variable- Area Sound Track on 16-Mm Koda- 
chrome," by R. G. Hufford and N. L. Simmons, Eastman Kodak 
Company, Hollywood, California, and R. V. McKie, RCA Victor 
Division, Radio Corporation of America, Hollywood, California 

"Bipack Photography," by Thomas Gavey, University of Southern 
California, Los Angeles, California 

"Make-up for Color Photography," by Hal King, Max Factor and 
Company, Hollywood, California 

"The Motion Picture Research Council Its Functions and Activi- 
ties," by W. F. Kelley, Motion Picture Research Council, Holly- 
wood, California 
8:00 P.M. Technical Session, Magnolia Room 

Session will open with a 35-mm motion picture short 

"Principles and Practice of Three-Color Subtractive Photography," 
by W. T. Hanson and F. Richey, Research Laboratories, Eastman 
Kodak Company, Rochester, New York 

"Masking in Color Duplication," by T. H. Miller, Eastman Kodak 
Company, Rochester, New York 

"The Analysis of Developers and Bleach for Color Reversible 
Film," by A. H. Brunner, Jr., P. B. Means, Jr., and R. H. Zappert, 
Research Laboratory, Ansco Division, General Aniline and Film 
Corporation, Binghamton, New York 
Adjournment of the 63rd Semiannual Convention 

Journal of the 

Society of Motion Picture Engineers 



Buying Carpet by the Pound .JOHN V. SMEALLIE 421 

Carpet Construction and Installation. . . .OLIVER P. BECKWITH 426 

Rubber Floor Coverings T. S. SAVOURY 433 

Carpet Wear Increased with Sponge Rubber 


Vacuum Cleaning of Theaters RICHARD WEBBER 439 

Maintenance of Hard Floor Coverings DANIEL FRAAD, JR. 442 

Optical Sound-Track Printing JOHN A. MAURER 458 

Use of G-3 Film-Processing Tank 


High-Intensity Projection Arc Lamp CHARLES A. HAHN 489 

Four-Channel Re-Recording System 


Committees of the Society 505 

Staff Changes 516 

Section Meetings 517 

Current Literature 518 

Book Reviews : 

" Applied Architectural Acoustics," by Michael Rettinger 

Reviewed by C. S. Perkins 520 

"Patent Notes for Engineers," by C. D. Tuska 

Reviewed by Irl R. Goshaw 520 


Chairman Editor Chairman 

Board of Editors Papers Committee 

Subscription to nonmembers, $10.00 per annum; to members, $6.25 per annum, included in 
their annual membership dues; single copies, $1.25. Order from the Society's general office. 
A discount of ten per cent is allowed to accredited agencies on orders for subscriptions and 
single copies. Published monthly at Easton, Pa. f by the Society of Motion Picture Engineers, 
Inc. Publication Office, 20th & Northampton Sts., Easton, Pa. General and Editorial Office, 
342 Madison Ave., New York 17, N. Y. Entered as second-class matter January 15, 1930 
at the Post Office at Easton, Pa. under the Act of March 3, 1879. 

Copyright, 1948, by the Society of Motion Picture Engineers, Inc. Permission to republish 
material from the JOURNAL must be obtained in writing from the General Office of the Society. 
Copyright under International Copyright Convention and Pan-American Convention. The 
Society is not responsible for statements of authors or contributors. 

Society of 

Motion Picture Engineers 

342 MADISON AVENUE NEW YORK 17, N. Y. TEL. Mu 2-2185 




Loren L. Ryder 

5451 Marathon St. 

Hollywood 38, Calif. 

Donald E. Hyndman 

342 Madison Ave. 

New York 17, N. Y. 

Earl I. Sponable 

460 West 54th St. 

New York 19, N. Y. 


Clyde R. Keith 

233 Broadway 

New York 7, N. Y. 

William C. Kunzmann 

Box 6087 

Cleveland, Ohio 

G. T. Lorance 

63 Bedford Rd. 

Pleasantville, N. Y. 

John A. Maurer 
37-01 31st St. 
Long Island City 1, 


N. Y. 


Ralph B. Austrian 
247 Park Ave. 
New York 17, N. Y. 

James Frank, Jr. 
18 Cameron PL 
New Rochelle, N. Y. 

John W. Boyle 

1207 N. Mansfield Ave. 
Hollywood 38, Calif. 
David B. Joy 
30 E. 42d St. 
New York 17, N. Y. 



Robert M. Corbin Charles R. Daily 

343 State St. 5451 Marathon St. 

Rochester 4, N. Y. Hollywood 38, Calif. 

Hollis W. Moyse 

6656 Santa Monica Blvd. 
Hollywood, Calif. 

William H. Rivers 
342 Madison Ave. 
New York 17, N. Y. 

Alan W. Cook 
4 Druid PI. 

Binghampton, N. Y. 


S. P. Solow 
959 Seward St. 
Hollywood, Calif. 


Lloyd T. Goldsmith 

Burbank, Calif. 
Paul J. Larsen 

Los Alamos Laboratory 
University of California 
Albuquerque, N. M. 

R. T. Van Niman 
4431 W. Lake St. 
Chicago, 111. 

Gordon E. Sawyer 
857 N. Martel St. 
Hollywood, Calif. 

Theater Engineering Conference 

Floor Coverings 

Buying Carpet by the Pound* 



Summary Carpeting is a major cost in the theater furnishing budget and 
is still greater in the maintenance and replacement program. An approach 
to a better understanding of this problem is a study from the angle of "Buy- 
ing Carpet by the Pound." 

FACED WITH A dozen or more vital points in specifications govern- 
ing the quality of carpet-fabric construction, a purchaser must 
have a rather simple but final rule to govern his selection not only be- 
tween offers made by different supply factors but also between the 
several types of weave constructions. Each type of weave requires a 
proper balance of pitch in the weft, rows, or wires per inch in the warp, 
pile height, yarn type, and size as well as the quality of the materials 

Realizing that as much as five sixths of the enormous tonnage of 
raw materials consumed in carpet production in the United States is 
imported, one can quickly appreciate that the major cost of the 
finished fabric is in the material with a relatively small percentage re- 
quired for the fabrication in labor costs and sundries. 

"Buying Carpet by the Pound" might, therefore, be suggested as a 
slogan to guide one in the decisions that will follow the use of more de- 
tailed formulas. 

No one element of construction makes a carpet but rather the 
proper co-ordination and balancing of all elements are necessary in 
order to produce a fabric of maximum value. First it is conceded that 
only virgin-wool stable of the accepted Class Three dutyfree govern- 
ment specifications type will be used for the surface yarns. Years of 
laboratory testing, long spinning experience, and fabric-wear tests 
both on machines and in traffic use will determine the proper blending 
of many types of stable in varying percentages to obtain the ultimate 

* Presented October 21, 1947, at the SMPE Convention in New York. 



perfection from the 200 or more kinds grown and imported from all 
the world continents. 

The first point to be determined might well be the advisability of 
selecting woolen or worsted yarn for the desired installation. While 
sheep wool will be used in both instances, the fibers will be selected, 
scoured, blended, and spun into the two forms of yarn to be woven 
into different types of' fabric, to be installed to serve different pur- 
poses, and to be maintained in different methods of procedure. 

Woolen yarn, forming the greater yardage in common use, is spun 
from fibers measuring from the shortest up to about nine inches in 
length. These are interlocked as much as possible in fifty-four motions 
on the carding machines and then rather tightly twisted in the single 
yarn. When piled up and used in a cut-pile weave, woolen yarn will 
resist the penetration of dirt particles. It can be distinguished easily 
by a tendency to shed the very shortest fibers upon close examination 
and use. 

Worsted yarn, in contrast, is spun from fibers between three quar- 
ters of an inch in length up to twenty inches or more after the shortest 
fibers have been combed out as noil and disposed of by the spinner 
as a by-product. Worsted yarn will be much smaller in diameter in 
the single strand than woolen and will have comparatively little twist. 
Worsted yarn will serve as the best form of yarn for most of the round 
wire or uncut looped pile constructions and the fibers will stand erect 
and parallel in the cut-pile constructions. Dirt particles will work 
down in the worsted-pile surface demanding more harsh and more 
frequent cleaning than woolen. 

The many weaves and myriad qualities in woolen will serve best in 
all general installations where traffic wear is expected. Worsted con- 
struction will serve best where traffic is excessive, where cleanliness is 
demanded, and where frequent cleaning is possible. As the spinning 
of worsted yarn might cost approximately one third per pound more 
than woolen to manufacture there must be a very definite reason for 
its selection. 

Long considered ideal for use in dining areas, Pullman cars, hos- 
pital installations, and the like, where woolen lint would be found 
objectionable, worsted is likewise of value in powder rooms, smoking 
lounges, and the like in theaters. 

Carpet quality may vary in a dozen specifications but at least five 
seem to be the most important. 

First, the pitch or the number of pile ends of surface yarn per inch 


of weft width of the fabric, which is usually noted as 189 pitch or 
seven tufts to the inch in the 27-inch basic width, as in the standard 
Axminster construction and many woolen qualities. In the finer 
worsted yarn the pitch would be greater, as found in a good quality of 
the Wilton weave with nine and a half tufts to the inch and known as 
256 pitch. 

Second, the number of rows of tufts to the inch in the warp direction 
of the fabric in the Axminster and Chenille weaves and known as 
wires in the Tapestry, Velvet, Brussels, and Wilton weaves. 

Third, pile height, which is ther actual height of the tufts of surface 
yarn from the top of the fabric to the backing material. 

Fourth, the pile yarn itself, whether woolen or worsted, and the 
size numbered according to- a standard table. The question of the 
number of plies in the yarn used develops, the thought that it is the 
density of the actual fibers that determines the wear of the finished 

The United States Bureau of Standards formula, that is accepted by 
the carpet trade, declares that the wear index varies as the square of 
the density times the height of pile, or the formula D 2 h indicating 
true value, with the height of pile covering only the luxury factor. 

Fifth, the general quality standards of all the materials used in- 
cluding the backing yarns which are a proper combination of vegetable 
fibers such as cotton, jute, and kraftcord. 

Carpet wool is a very rough, absorbent type of fiber which has a 
tremendous affinity for color matter allowing the use of twenty thou- 
sand shades of color or a many tunes greater number than any other 
fiber or forms of color use. Every crystal of dye used to obtain a de- 
sired color will be absorbed by the fiber adding bulk, weight, and wear. 
Again, wool is the highest in hydroscopic or moisture weight and will 
vary constantly with the changes in the surrounding atmosphere. 

There are five general types of weaving methods in common use 
today. All will furnish suitable fabric constructions, color, and de- 
sign accomplishments as well as meet different budget figures in 
theater furnishings. These weaves are not competitive but they will 
overlap in the price brackets. They can be woven and sold from 
approximately 50 cents per carpet yard to $94.50 per square yard 
which was recently quoted for a theater-lobby rug in custom-order 
Chenille hand-carved to outline angelic figures in intaglio. 

The weave names can be associated with the fingers on one's hand 
in order to place them in their relative price brackets. On the little 


finger we can place the Tapestry round-wire weave as the lowest in 
the price scale and woven to meet the humblest budget. Worsted 
yarn and a chrome-set dye are commonly used when pattern is de- 
sired. This weave will give remarkable service with the traffic wear 
falling on the side of the yarn loops. 

The second or ring finger will indicate the cut-pile Velvet weave 
where we find the volume yardage of plain or solid-color production 
from beams of yarn supplied as warp. Here again, the woolen or 
worsted yarns that are used must be chrome-dyed to withstand the 
scouring out of the flour used in applying the dye in patterned goods. 
Steam-set twisted yarns give splendid service in this weave. 

The middle finger will indicate our only American invention in 
carpet-loom production, Axminster. Woolen yarns are used in un- 
limited color range to furnish almost one half of the'total yardage in 
this middle price bracket. 

The index finger will indicate the Jacquard Wilton weave where 
delicacy of design and a sense of luxury can be accomplished with the 
use of the Jacquard pattern control. The pile yarns, that are not 
needed to form the pattern will be bound in the body and back of the 
construction giving this weave the concealed quality or cushion back 
that assures softness underfoot and a long-wear life. These four con- 
structions furnish the popular demand and are woven on semiauto- 
matic looms usually operated by small individual electric motors. 

The thumb, in turn, will indicate custom-order Chenille, which is a 
twofold weave requiring a hand-tufting operation in the second 
weaving process. This type is known as "the weave of unlimited 
possibilities." It is woven up to thirty feet in width, seamless, any 
length, any shape, any coloring, and any design in woolen or worsted 
yarns or combination thereof. Popular in rug form or complete carpet 
coverage in theater lobbies, foyers, lounges, and other public spaces, 
this weave is finding new uses constantly through its versatility. 

The modern texture trend allows for carved, embossed, etched, 
sculptured, or intaglio effects in cut-pile constructions. Irregularity 
of pile in both looped and cut-pile surfaces often gives added third- 
dimensional decorative effects. Many of these up-to-the-minute 
creations as well as special designing and coloring to suit architec- 
tural decorative desires can be obtained at no added per-pound cost. 

With all these facts in mind a purchaser of carpet can appreciate 
that actually he is buying carpet by the pound. Also believing that 
no carpet is any better than the ultimate service that it renders, he 


will be concerned further in the proper installation and maintenance. 
Absolutely smooth floor surfaces must be assured, for the slightest 
irregularities show up immediately in the fabric surface. The proper 
underlay should be chosen on the basis of budget cost which might be 
twenty per cent, rather than the mistaken idea that a thick or par- 
ticularly resilient cushion will redeem an inexpensive carpet. 

The use of modern tacking strips, such as Roberts Smoothedge, for 
example, will cost less than drilling and doweling holes in concrete 
floors. The use of these patented strips will allow for refitting or re- 
moval for cleaning more readily than former tacking and fastener 
methods used. 

It has been proved that clean carpet will outwear dirty fabric. It is 
well to set up very definite rules for maintenance. Worsted cut-pile 
weaves should be cleaned harshly and often in order to extract the 
dirt crystals that have seven to seventeen cutting edges which will 
cut the wool fibers in traffic wear. Woolen cut-pile weaves should be 
vacuumed regularly as deemed necessary. As wool fibers have such a 
high moisture weight it must be assured that the needed water vapor 
will be carried in the surrounding atmosphere to guarantee a satis- 
factory wear life. Where air conditioning or control systems are func- 
tioning properly the carpet will render remarkable service. 

Theater Engineering Conference 

Floor Coverings 

Carpet Construction and 



Summary The factors affecting the service and wear of pile floor cover- 
ings are discussed, particularly in relation to theater carpets and rugs. An 
attempt is made to show how this information can be exploited by the theater 
operator to his own advantage in terms of obtaining longer wear and less 
replacement from his carpet. 

AND RUGS are not inventions of the nineteenth and 
twentieth centuries. They have been made by man for thou- 
sands of years to cover the floors of his home, whether it be a tent or a 
palace, a bungalow, or a mansion. Their manufacture, until recent 
times, has been an art in which the required skills were handed down 
from father to son. 

Carpets and rugs suitable for public buildings, where the traffic 
over them amounts to hundreds of thousands of people per year, are 
creations of the twentieth century. While their color, design, and 
appearance are created by the artist with his age-old heritages from 
the masters of every century, their ability to receive the brutal 
punishment of thousands of footsteps for many years, and to retain 
their original beauty is an achievement engineered into them on the 
basis of knowledge developed in the modern laboratories of America. 

The theater operator needs to know the factors of carpet construction 
and installation affecting wear. Any moderate-sized theater has an 
investment of hundreds of dollars in its floor coverings. Poor per- 
formance not only means the added costs of too frequent carpet re- 
placement but costs of installation as well, by no means an insignifi- 
cant amount. Then, too, intangible liabilities are created from 

* Presented October 21, 1947, at the SMPE Convention in New York. 




wornout appearance and condition, customer reaction, and some- 
times accidents and claims. 

It might be in order at this time to classify the quality character- 
istics of carpets and rugs. These are shown in Fig. 1. It will be 
noted that the left-hand side relates the aesthetic wants; as these fall 
within the province of the 'artist and designer, not the engineer, we 
shall not consider them here. The right-hand side lists the practical 
wants, those of service and wear. In this paper we shall concern 
ourselves with two of the three items under service and wear, wear 
life and durability of original structure. Time does not permit discus- 











SMOOTH wess 














Nfi BY 

5 IN 




iNJtcT arracK 


'.uwFflct out TO 







FIG. 1 Classification of the quality characteristics of carpets and rugs. 

sion of the third, durability of original appearance, although it is a 
subject important enough to warrant a separate paper. 

Wear life of carpet, that is resistance to rapid change in surface- 
caused abrasion by traffic, is affected by four things. 

1. The kind of fiber used in the surface. 

2. The processing to which the fiber has been subjected. 

3. The construction in which the carpet has been woven. 

4. The manner of installation. 

Practically all pile floor coverings used in theaters today are made 
with a surface of carpet wools. These wools are imported into the 
United States since they are not raised here. They come from every 
continent and there are 200 or more different kinds and types. The 


wear resistance of the various wools has been the subject of con- 
siderable study and research. Testing equipment developed by the 
United States National Bureau of Standards and by laboratories of 
carpet manufacturers has enabled the engineer to evaluate the wear 
life of the wools used as some carpet wools are longer wearing than 

The manner in which the wools are processed during the fabrication 
of carpet affects the amount of wear obtained from the fiber. Wools 
have to be scoured in strong alkalies, dried at high temperatures, 
dyed in the presence of strong acids and at high temperatures, twisted 
and distorted in spinning, and stretched in weaving. All these things 
can reduce the amount of wear inherent in the original fiber if these 
operations are not rigidly controlled. As early as 1930 experimental 
work was performed which showed that prolonged boiling in water 
alone made tremendous reductions in the wear life of carpet whose pile 
yarn had been so treated. 1 

The foregoing two points are things which the buyer and user of 
theater carpet cannot control in the selection of his floor covering. 
He must depend on the technical skill of the manufacturer from whom 
he buys. Therefore his only safeguard that the fabric he buys con- 
tains the longest wearing wools, processed so as to retain practically 
all of their inherent wear value, is to know the extent to which the 
carpet manufacturer carries on research and development activities 
devoted to this end. 

The construction in which the carpet has been woven plays a 
tremendous part in the wear life obtainable from if. Wear is a function 
of the amount of wool woven into the fabric ; the more wool, the longer 
wear life. But the surface form in which the wool is woven into the 
fabric plays an important part in the wear life. It can be said that 
there are "two factors of form which affect the amount of wear ob- 
tained. These are the density of the pile or the nap and its height. 
Research work 2 " 4 at the National Bureau of Standards has shown 
that, all other factors being constant, the wear index of a carpet 
varies as the square of the density times the pile height as shown in 
Fig. 2, taken from Research Paper 3 No. 640 of the National Bureau of 
Standards. Wear index is the number of thousands of revolutions of 
the wear-test machine required to wear out the carpet, i. e., reduce it 
to a mathematically determined end point. Translated into everyday 
terms this means that if one carpet is twice as dense as another, other 
things being equal, it will wea r four times as long. On the other hand, 




if one carpet has twice the pile height of another, other things being 
equal, it will wear only twice as long. 

A practical lesson to be learned from the foregoing data is that when 
a theater operator buys a pile floor covering for wear and the choice is 
between two fabrics of about the same pile height, he should buy the 
fabric of the highest density. Another factor of importance to the 
theater operator when buying carpet for wear is the efficiency with 
which all of the wool woven into the fabric is used ; wool is the wearing 
surface; it is the most costly component of the carpet; hence, for 
maximum wear value per dollar as much of the pile wool as possible 
should appear on the surface of 
the carpet. 

The Velvet weave has a dis- 
tinct advantage in that prac- 
tically all of the wool yarn used 
in the rug appears in the surface 
and this advantage has given it 
its pre-eminent place wherever 
long wear is the outstanding 
quality characteristic desired. 

The manner in which carpet is 
installed affects the amount of 
wear that can be obtained from 
it. Underlays increase wear life 
because they absorb some of the 
energy expended on the carpet 
by the action of moving feet. 
Without the underlay the carpet 
absorbs all the energy and this promotes the process of wearing 
out more rapidly than if underlays were used. 

Some underlays are more effective than others. Sponge rubber, for 
example, does a better job of prolonging carpet wear than felt. The 
reason for this is that sponge rubber is more permanently resilient. 
After considerable traffic the felt underlay compresses and loses much 
of its original thickness. Consequently it is then unable to absorb as 
much of the energy imparted to carpet by traffic as it did originally. 
On the other hand, sponge rubber, after an equal amount of traffic, 
will retain practically its original thickness and original ability to 
absorb energy. 

Fig. 3 shows laboratory wear tests of carpet without underlay, with 

FIG. 2 Correlation of wear index 
with product of density squared and 
pile height. 




a felt underlay, and with a sponge-rubber underlay. It will be noted 
that the felt underlay increased the wear 36 per cent over that of the 
same carpet without an underlay, but the increase from sponge 
rubber was 70 per cent. 

The above results have been corroborated by service experience. In 
several installations on theater stairs it was found that carpet under- 
laid with 1 / 2 -inch sponge rubber lasted twice as long as carpet laid 
with 64-ounce felt. 

One factor of carpet installation to which theater operators and 
carpet layers need to devote more attention is the protection of carpet 


FIG. 3 Effect of underlay on wear- test index of carpet. 

in areas where traffic is likely to be highly concentrated. For example, 
traffic will be much greater at the point where tickets are collected 
than at other areas, as at doorways, particularly narrow ones, where 
traffic is concentrated. On stairways that curve or change direction 
it will be found that most of the traffic takes the shorter arc. In loca- 
tions such as these, extra provision should be made to protect the 
carpet. If it is a level area sponge rubber might be used in place of the 
felt used in the rest of the installation. If the area is on the stairs 
where the installation already calls for sponge rubber, use of a more 
dense rubber than on the rest of the stairs might be made. If no 
special precautions are taken to protect these areas then they should 
be frequently examined to determine the condition of the underlay. 


Replacement should be made if there are evidences of marked loss in 
thickness of the underlay. 

Durability of original structure affects carpet performance more 
than is realized. The ideal theater carpet is a relatively rigid struc- 
ture whose backing yarns are for the most part inextensible materials 
such as jute or kraftcord. To cite an analogy, nylon, which can be 
molded readily as a plastic, is as high in tensile strength as some of our 
best steels. However, nylon could not be used as a construction 
material or for making machinery because it lacks the rigidity of steel. 
Carpet of every conceivable form of pile surface can be made with 
soft nonrigid backing materials. However, if this were put in use in a 
place such as a theater it would soon stretch, giving unsightly and 
hazardous ripples. This is particularly true in sloping aisleways of the 
orchestra section. The lengthwise stress on a carpet in such a location 
is very high and excessive stretching will take place if the back struc- 
ture is not sufficiently rigid. 

Installation conditions occasionally affect durability of original 
structure. Sometimes it occurs that a stairway having a very 
narrow tread, 10 inches or less, has to be carpeted. In such cases, it 
often happens that tufts are gouged out of the carpet on the riser area. 
This occurs because with a tread as narrow as this the heel of the foot 
in descending must necessarily scrape heavily over the riser portion. 
Where narrow-tread stairs are to be carpeted this condition should 
be watched for as time progresses. It is generally possible to replace 
tufts without difficulty if the condition is caught before it becomes 

Indiscriminate wetting of carpet can result in serious damage to the 
floor covering. When the backing structure gets wet, as might occur 
in areas near drinking fountains and street doors, or after a carpet has 
been carelessly floor-shampooed, mildew may develop. This is 
particularly true in summer weather when high humidities prevent 
rapid drying. Dampness, darkness, and relatively high temperatures 
are ideal conditions for the growth of cellulose-destroying fungi. 
These microorganisms so lower the strength of the cellulose backing 
yarns that the carpet literally falls apart. While antiseptics are being 
developed for the application to the backing yarns of carpet, there is as 
yet no treatment that will provide complete mildew resistance under 
all conditions of use. 

In conclusion it is hoped that this presentation has demonstrated 
the wealth of technical and engineering data available on carpet for 


theaters which have been collected in the laboratory. The able 
theater operator could exploit this knowledge to his own advantage in 
terms of obtaining longer wear and less replacement from his carpet. 


(1) A. Griffin Ashcroft, "Comparison of values in soft floor coverings," Mel- 
liand Textile Monthly, vol. 4, pp. 721-724; March, 1933. 

(2) H. F. Schiefer and A. S. Best, "Carpet wear testing machine," Bureau of 
Standards Journal of Research, vol. 6, pp. 927-936; June, 1931, RP 315. 

(3) H. F. Schiefer and R. S. Cleveland, ' 'Wear of carpets," Bureau of Standards 
Journal of Research, vol. 12, pp. 155-166; February, 1934, RP 640. 

(4) H. F. Schiefer, "Wear testing of carpets," Bureau of Standards Journal of 
Research, vol. 29, pp. 333-379- November, 1942, RP 1505. 

Theater Engineering Conference 

Floor Coverings 

Rubber Floor Coverings* 



Summary The most important problem with which theater operators 
have to contend is maintenance, i. e., the prevention of dirt, grit, slush, and 
moisture from being carried into the theater proper so as not to mar the de- 
sired clean atmosphere. 

Rubber floor coverings of every description have been universally used for 
this purpose because of the material's ability to stand up under the most 
adverse conditions. These coverings consist of corrugated mattings, perfo- 
rated mats, link mats, rubber tile, and sheet flooring. There are various types 
of each, and all are designed to serve definite needs. 

BASICALLY ALL rubber floor coverings are made of natural, syn- 
thetic, or reclaimed crudes. These crudes are mixed with 
other ingredients, such as fillers, pigments, and vulcanizing agents. 
The compounds formed are then vulcanized under extreme heat and 
pressure. The surface designs, such as corrugated, pyramid, or a 
smooth slick finish are accomplished by molds used in the vulcaniza- 
tion process. There are a wide range of thicknesses available from 
3 /32 to 1 /z inch to meet any flooring requirements. The use of mats 
and mattings is governed for the most part by location. 

Let us consider the outer lobby first. What is desired of a rubber 
floor covering in the outer lobby? First of all, it should prevent 
slipping, second, it should pick moisture and grit off the patrons' 
shoes before the carpeted areas are reached, and third, it should be 
decorative, so that it will harmonize with your color schemes. All 
three purposes can be achieved with custom-made corrugated and per- 
forated mats. Corrugations prevent slipping and act as silent foot 
scrapers. Perforations catch the grit and help keep it off the surface. 
Decorative schemes can be accomplished by variations in color and in- 
laid design. Experienced mat manufacturers today can produce prac- 
tically any design in an almost unlimited variety of color combinations- 

* Presented October 21, 1947, at the SMPE Convention in New York. 


434 SAVOURY May 

Corrugated and perforated mats are generally made 3 / 8 or 1 / 2 inch 
thick. They are reinforced in the center with heavy, specially treated 
duck which prevents the mats from stretching out of shape, and in- 
creases their service life appreciably. While link mats can be used for 
the same location and service, they lack some of the features of the 
perforated and corrugated type. The most commonly used type of 
link mat is made of extruded rubber that is cut into small segments 
and assembled by wires. But decorative possibilities are limited. 
The rubber is not reinforced with fabric. Wires are subject to rust, 
corrosion, and distortion, thus shortening service life. 

In the inner lobby, there is a great advantage in the use of custom- 
made perforated and corrugated mats. In addition to the features 
just pointed out, these mats are highly abrasion-resistant and have 
outstanding wearing qualities. They are relatively easy to maintain, 
because they can be taken up, cleaned, and relayed at frequent inter- 
vals, and they are sanitary. Inner-lobby mat designs and colors can 
be made to harmonize with interior decoration or to vary from those 
used in outer lobby mats, if desired. 

Powder rooms and smoking rooms present different problems. 
Here either sheet flooring or rubber tile should be used, provided the 
floors are "above grade." These materials should never be used on 
or below grade where no air space is provided under the subfloor, and 
consequently where sweating is likely to occur. Sheet flooring and 
block tile can be made in practically any color, tone, or shade de- 
sired. Therefore a wide variety of color and design combinations can 
be accomplished with them. Both are usually made with highly 
polished surfaces and must be waxed frequently. Either sheet flooring 
or block tile must be cemented down by skilled experts, and not by the 
amateur. Rubber tile is made in blocks ranging from 4- to 36-inch 
squares and in thickness ranging from 1 / 8 to */ 4 inch. 

Although sheet flooring used in theaters customarily is V' 8 inch 
thick, other gauges can be made ranging from 3 / 3 2 to y 4 inch. Sheets 
usually are 36 inches wide and 25 yards long. 

There is, however, a special type of sheet flooring that has unusual 
possibilities for theater use. With this type, intricate designs can be 
reproduced by assembling segments having different colors and shapes 
and vulcanizing the entire combination into an inseparable unit at the 
factory. Consequently, an entire floor covering of attractive design 
can be shipped in large units and laid without cementing. The 
surface of this type is not highly polished but has a suedelike finish 


and has the soft appearance of a carpet. This contributes to safety, 
since it prevents slipping. 

Sheet-rubber flooring can be used to advantage on steps and risers. 
Here, too, the long-wearing quality and easy maintenance of sheet- 
rubber flooring of correct construction Avill contribute to economy. 
Color can serve as an additional function, it can brighten and call 
attention to the stair edge, especially where soft lights are used. For 
instance, a narrow, brighter-colored contrasting strip can be inserted 
at the edge of the tread, and, of course, color harmony as well as 
safety can be accomplished. 

Rubber nosing is used to prolong the life of carpet on stairs. 
Normally the edge of the carpet wears more rapidly than the flat 
surfaces. Frayed edges are not only unsightly but dangerous, and 
can cause tripping. In most cases nosings are used on steps where 
carpet has already frayed. The worn portions of the carpet are cut 
out across the full width of the tread, the nosing is then cemented to 
the step almost up to the edge of the remaining carpet, and the carpet 
tacked down over a recessed lip of the nosing. This makes a flush 

In the aisles and seating area, rubber should not be used, except in 
two cases. The two exceptions are first, the rubber-matting runner, a 
commonplace temporary covering. Its chief function hi this area is to 
protect carpeting in bad weather. Most runners are made of re- 
claimed rubber and are generally made in black or maroon. They 
should have cloth insertions or cloth backs to prevent distortion and 
to prolong their life. The second exception is rubber underlay or 
lining which will be covered in the following paper. 

Although considerable research work has been done toward de- 
veloping practical rubber floor covering that is as quiet as carpet, we 
do not as yet believe that the problem has been solved. Therefore, we 
refer you to our friends in the carpet industry. 

Theater Engineering Conference 

Floor Coverings 

Carpet Wear Increased with 
Sponge Rubber* 



Summary As is well known, sponge rubber as such, has been in use for 
many years in a variety of articles. And like so many other things made of 
rubber, great strides have been made in scientifically improving its com- 
pound to suit different conditions and circumstances. 

FOR MORE THAN ten years sponge rubber in sheet form has been 
used as a carpet cushion until today a very large percentage of 
the production of sheet sponge rubber is. used for this purpose. Re- 
peat orders from the same users who started with it ten years or more 
ago prove conclusively that sponge-rubber cushions make carpets 
wear longer. 

There are several reasons for this. First, rubber recovers or re- 
turns to its original thickness completely, whereas under pounding 
heels, other materials, such as hair lining or hair and jute, mat down. 
The mere fact that sponge rubber recovers its height completely and 
continuously naturally protects the carpet no matter how much 
pounding it receives. Second, in order to accomplish that super-lush 
softness many theaters resort to extra thick padding, with the result 
that people's feet sink too deep and since most of us do not lift our 
feet very high in our natural stride, the shoes scrape the carpet surface 
slightly thereby causing unnecessary wear on the carpet surface. 

While produced in thicknesses of from 3 / 32 to 1 inch, for average 
locations, the carpet cushion in V 4 -inch thickness is recommended 
and for areas where extra thickness is desired 3 /8-hich thickness is 
ample. It is produced in rolls of approximately 20 yards in 36- and 
53-inch widths. 

When used on stairs sponge rubber has extended the life of carpets, 

* Presented October 21, 1947, at the SMPE Convention in New York. 


especially at the edge where the wear is greatest. A report issued re- 
cently by an outside testing laboratory regarding the results of tests 
conducted on different types of padding states: "There have been a 
number of inquiries recently about the efficiency of sponge rubber as 
a carpet underlay versus other underlay products. Our laboratory has 
forwarded information which summarizes tests made on installations 
of stair carpet using different underlays. Eight underlays were tested 
including three jute, two jute-hair, one cotton-paper, and two sponge- 
rubber underlays. As compared to an installation without under- 
lay it was found that a jute-hair underlay of 0.42 inch in thickness 
gave the same increase in wear to the carpet as a sponge-rubber pad of 
0.23 inch in thickness. However, during the test the sponge rubber 
maintained its thickness whereas the jute-hair pad reduced in thick- 
ness nearly 50 per cent. When the jute-hair pad mentioned was 
reused the increase in the carpet's wear life as compared to carpet 
without underlay was only about one half of the increase obtained 
when the new jut.e-hair pad was used. As shown by this test it is un- 
doubtedly preferable to install new padding than to reuse the old. 
Because sponge rubber maintains its thickness under use and reuse it 
has a distinct advantage in this characteristic." 

This sponge rubber is compounded of crude rubber and comes in 
black with a red marbleized design. The odor of rubber has been re- 
moved and a faint pleasant aromatic scent has been added. It is 
easily laid directly to the floor, and can be bonded with the usual 
water-soluble glue. The edges are trimmed square and can be abutted 
with a pressure adhesive tape. The carpet laid over it should extend 
about 3 / 4 inch beyond the edge of the sponge-rubber underlay and 
anchored in the conventional way. 

Sponge rubber has unusual gripping qualities and prevents carpets 
from slipping and creeping. This is especially noteworthy since most 
aisle carpets have a tendency to bunch up at the foot of the aisle. 
Sponge rubber anchors the carpets and prevents this common diffi- 

Carpets can be cleaned better and easier since grit cannot get into 
the sponge rubber and whatever does filter through the carpet goes no 
farther than the surface of the sponge and most of this is drawn out 
with vacuuming. 

Also, sponge rubber is repulsive to vermin. There is nothing to feed 
on nor is there any way for vermin to get into it, the skin surface is 
impermeable and the pore structure is only partially porous. 


Attention is drawn here to a very important point. You will note 
that this product is referred to as sponge rubber. The spongy pore 
structure of this product is accomplished with chemicals which react 
on the rubber in the curing process causing it to expand and form 
pores within the stock. These pores are only partially intercon- 
necting and both surfaces there is no right or wrong side are 
impermeable. This is as it should be for undercarpet application. 
Particular attention should be given to the difference between this 
chemically blown sponge designed for undercarpet cushions and 
foam rubber. While this could be called sponge rubber too, it is 
never referred to as such because of its totally different character- 
istics. Foam rubber is completely different from any other class of 
rubber in that it is porous through and through. The pores within the 
stock are entirely interconnecting, and both surfaces are also porous. 
You can blow air and smoke through it and you can pour water 
through it. Because of this extreme porosity it is ideal for seating, 
mattresses, and pillows, since it easily dissipates body heat. 

The chemically blown sheet sponge rubber designed for carpet 
underlay has been in use in theaters, hotels, and Pullman cars since 
prewar days and as a result has grown remarkably in popularity. 
Where it came in contact with heater pipes along the edge of Pullman 
cars it had a tendency to crystallize slightly but the migration of this 
crystallization was confined to within an inch of the edge of the rub- 
ber and when rehabilitation work was necessary on the cars, no 
sponge-rubber cushioning was required to be replaced. 

This product is now in production and is currently available 
throughout the country. 

Theater Engineering Conference 

Floor Coverings 

Vacuum Gleaning of Theaters* 



Summary This paper discusses the maintenance of soft floor coverings 
and its related subject, vacuum cleaning, and outlines the type of vacuum 
cleaners now available for theater cleaning, and their proper uses and main- 
tenance, so that the carpets in theaters are always kept immaculately clean, 
the ever-present problem of the theater manager. Also it will attempt to 
show how expense in connection with the renewal of carpets and the cost of 
its maintenance can be held to a minimum by the use of properly designed 
vacuum-cleaning equipment. 


ETERIORATION in a carpet depends, of course, on the amount of 
traffic over its surface. The gradual thinning of the nap of the 
fabric is caused, however, mostly by imbedded sharp grit with nap- 
cutting action as the foot passes over the surface. Therefore, it is im- 
portant that whatever cleaning medium is used it have sufficient 
power to remove the grit as well as the dust. For over 40 years the 
vacuum-cleaning industry has progressed steadily designing machines 
to meet the cleaning problems encountered in theaters. The problem 
today is that of selecting the vacuum-cleaning machine best suited to 
the specific need of the theater. 

In considering vacuum cleaners, the first requirement is that it has 
to clean. Any other prevailing advantages it may have otherwise are 
worthless. Then we should consider the cost of labor, maintenance, 
power consumption, maneuverability, initial cost, and deterioration 
of the equipment. These are not listed in their proper sequence of im- 
portance, for what may be important to one manager may not be to 
another, but what is equally important to all is that there is an ever- 
present problem of cleaning the theater thoroughly, and to do so at a 
reasonable maintenance cost. 

Basically there are several types of vacuum cleaners available, 
the stationary vacuum-cleaning system, commercial portable vacuum 
cleaners, and domestic portable vacuum cleaners. 
* Presented October 21, 1947, at the SMPE Convention in New York. 


440 WEBBER May 

The stationary type, frequently referred to as the central or in- 
stalled system, consists of a vacuum producer and dirt separator, 
both of which usually are located in or near the boiler room, with 
piping installed throughout the theater, having hose-connecting 
outlets so located that a porter using a 50-foot length of l l / 2 -inch 
diameter hose can reach and vacuum any part of the auditorium, 
mezzanine, balcony, sound screen, organ loft, fly gallery, in short, the 
entire theater. The initial cost of installing a stationary system is 
high as compared with the price range of the commercial portable 
vacuum cleaner, and more so as compared with the domestic port- 
able vacuum cleaner. Yet it must not be overlooked that the 
incredible low maintenance of this system invariably offsets the high 
initial investment, for it is a fact that in a great many theaters 
after thirty years of service the stationary systems are still in good 
working order. 

The low maintenance cost of this system is attributed to the fact 
that the vacuum producer is equipped with either a squirrel-cage or 
direct-current motor using electricity from the power service and not 
from the light system. This is an advantage because the motor in 
this case operates at 3500 or 1750 revolutions per minute, which is 
considered a slow operating speed and requires a minimum amount 
of maintenance, only requiring lubrication of the two motor bearings 
by the engineer every month or so. There are no wearing parts that 
have to be replaced, and also there are no problems such as frequently 
occur with any type of portable, such as having the equipment mis- 
used by the porters, parts such as wheels and castings broken through 
carelessness in handling, or the lack of maintenance of the motor which 
is overlooked and eventually results in expensive repairs and putting 
the portable cleaner out of service; usually when badly needed. 

The stationary system also is the most sanitary means of cleaning 
because as the dirt and litter are sucked up by the cleaning nozzle from 
the carpets they are carried through the hose, through the piping, and 
eventually deposited in the dirt separator in the boiler room. The 
foul air, after passing through the vacuum producer, is discharged 
into the boiler flue, leaving the theater "clean-smelling." 

The commercial portable vacuum cleaner, also known as the tank- 
type, primarily is designed for continuous heavy-duty service, em- 
bodying to a* lesser degree some of the advantages of the stationary 
system mentioned before in connection with suction and dirt ca- 
pacity, and the compactness and portability of the domestic type. 

Many different makes of commercial portable vacuum cleaners are 


available varying in cost and efficiency, each make being of a different 
type of construction and general design, using different types of 
motors, size of dirt receptacles, and filter bags, all designed to operate 
on the lighting circuit, which is usually 110 volts, single-phase, and 
therefore, usually equipped with a Universal-type motor, from 1 / s to 
l J /2 horsepower. It is important to remember that the speed of these 
motors will vary from 7000 revolutions per minute to a high 12,000 
revolutions per minute, and the higher the speed of the motor the 
greater the wear of the motor brushes and wearing down of the com- 
mutator, with, unless given very frequent maintenance, the eventual 
burning out of the motor, and the machine out of service. That is 
what we mean by high maintenance. With the commercial cleaner, it 
is important that it have a liberal dirt pan and filter bag of ample 
size, and have efficient suction at all times, in order to permit the con- 
tinual operation by the porter to do a good cleaning job without hav- 
ing to stop and shake the filter bag and empty the dirt receptacle too 

The domestic type of vacuum cleaning has been of great value to 
the housewife the world over, but when considered for use in a theater 
it should be remembered that this type has been designed primarily 
for limited duty. There are innumerable makes available, both in the 
upright and tank types. f 

The disadvantage of either of these types is the fact that they have 
extremely high-speed operating motors varying from 13,000 revo- 
lutions per minute to 16,000 revolutions per minute, and therefore the 
cost of repairs, replacement of motor bearings, switches, cords, and 
general servicing is frequent and high, and their efficiency is very low 
due to their small dirt capacity and low suction. 

It has been proved by laboratory tests that, to do the best job, 
the proper suction at the carpet nozzle for removing dust and grit 
is 39-inch water lift, sometimes referred to by its equivalent, 3-inch 
mercury lift, or ! 1 /2-pound lift, and the cleaner that comes nearest 
to this requirement is the right machine for the theater. 

In conclusion, the stationary system in all cases, no matter by 
whom manufactured, gives the desired results just outlined, and 
makes possible the thorough and most sanitary means of cleaning the 
theater. The commercial portable vacuum cleaner will vary con- 
siderably depending on the make selected. This domestic portable 
vacuum cleaner has an extremely limited place in theater cleaning. 
Its only advantage is the low initial cost but this definitely is offset by 
its limited efficiency and high maintenance cost. 

Theater Engineering Conference 

Floor Coverings 

Maintenance of Hard 
Floor Coverings* 



Summary The maintenance of hard floors has many aspects, but this 
paper will be restricted to telling how floors can best be cleaned, scrubbed., 
and waxed in order to maintain for them an attractive appearance. 

THE TERM "maintenance" is a broad one that has many meanings. 
To an airplane mechanic, it conveys the thought of maintaining 
a motor. To a roofer, it means roofing. To a plumber, it means 

Even cleaning is not so concrete a thing to talk about as one might 
think as there are no specification^ for it. One can talk of the weight 
of a rug and the height of the pile, or one can talk of a pilot-tube read- 
ing on a vacuum cleaner. But what is "clean"? What standards are 
there for cleaning? Before trying to clean a floor, therefore, it must 
be determined what degree of cleanliness is desired, which will be 
clarified later. 

To maintain a hard floor at the highest level of cleanliness, it 
would have to be covered with antiseptics every tune someone walked 
across it. If, under those standards, anyone had the temerity to 
expectorate on that floor, the entire building would have to be put in 
an autoclave. 

The author has not had many experiences in maintaining theaters, 
but has had some which may better illustrate the point about degrees 
of cleanliness. During the war, the author's company was called to 
Oak Ridge, Tennessee, as consultant on maintenance. Among other 
things, they were struggling with a problem in a small motion picture 
theater there. The last row of seats was flush against a beaverboard 

* Presented October 21, 1947, at the SMPE Convention in New York. 



partition. Right behind and above each seat was a large grease spot 
from the heads of people who sat in this last row and naturally leaned 

"We use this theater Sundays for church services and the lights are 
on," they said. "It is quite unsightly to have these smears behind 
each seat. How would you suggest that we clean them?" 

Beaverboard is very porous and hence resistant to solvents. It is 
not only difficult to get oil out of beaverboard, it is practically im- 
possible. It was, therefore, suggested that a good quality mineral oil 
be used to wipe the whole beaverboard partition. The problem was 
solved not by removing the spots by cleaning, but by uniformly dirty- 
ing the wall. 

Thousands of stores and other establishments that have light- 
colored hard floor coverings furnish another composite example. 
They are swept daily but mopped thoroughly only once a week, 
probably on Saturday night. Bright and early Monday morning the 
floor is beautifully white or light, then it starts to tone down and 
down until about Friday it is a pleasant-looking gray. The floor has 
been maintained reasonably. Extreme measures have not been taken 
to clean it, but proper health safeguards have been taken. True, 
these floors are not antiseptic, but no one expects them to be. 

A curious thing about floors is that after many have been dealt with 
it will be discovered that each develops a personality of its own. 
Identical terrazzo floors put down by the same company in the 
Pennsylvania Station and the Museum of Modern Art are as different 
after the passage of a little time as a dead-end kid and little Lord 
Fauntleroy. One has been toughened and hardened by the careless- 
ness of rushing, shoving thousands of careless commuters and 
travelers. The other remains dainty and ladylike as though blooming 
tenderly in response to the careful, gentle tread of art lovers with time 
on their hands. 

The same may have been found in theaters or movie houses. In one 
section of town, the theater will be genteel because its frequenters are 
respectful of property. They might even be people who would no.t 
think of throwing chewing gum on the floor, certainly not without 
first wrapping it in paper. But in another part of town one might be 
lucky to have the seats still attached after a Saturday matinee 
attended by young ladies and gentlemen of teen age and less. Here 
the floors will reflect a far different personality, possibly one hardened 
even to bubble gum. 

444 FRAAD May 

Then, there are climatic factors which strongly affect the per- 
sonality of hard-covered floors. The same floors in Montreal in the 
winter and in Palm Beach get different treatment, therefore have to be 
given different treatment in cleaning. In cities where there is snow 
on the ground most of the winter, it is necessary to cope not only with 
snow brought in, but with salt and snow which are tracked in, and 
must be cleaned differently than the light dust which is the most 
found at Palm Beach. 

With the foregoing factors in mind, the one thing which will help 
most in solving some individual floor problem is the cleaning com- 
pound used. Irrespective of whether cleaning is done manually or by 
a scrubbing machine, the cleaning compound used will determine the 
efficiency of your operation. 

To be more specific, the detergents or sequestering agents hi a 
cleaning compound will determine whether cleaning is efficient and in- 
expensive or inefficient and expensive. The better the detergents, 
soap powders, or particular compounds used for a particular job the 
less will be paid for manpower or the less the electric bill will be for 
using a scrubbing machine. 

It has been found in maintaining many floors that the grea-test 
efficiency is obtained by the use of properly compounded materials, 
usually custom-compounded for particular types of jobs. 

There are all sorts of cleaning compounds, such as soaps, on the 
market. They are all good for particular purposes. But none are good 
for all purposes. That is why care must be taken to use the right 
cle ner for the particular type of floor covering to be cleaned. 

The way surface-reducing agents or water softeners (the compounds 
mentioned above) work, is as follows. The man with the mop spreads 
out the water containing the cleaning compounds, which should re- 
duce surface tension, dilute the dirt, and begin to float it off the floor. 
If the compound does its work properly and softens the water, the 
mop slips easily and the worker accomplishes more. . If the com- 
pounds are wrong, the mop lacks an easy slip, the man works too 
h'ard, and accomplishes less. 

Among the best bases for many cleaners is trisodium phosphate. 
As a matter of fact, it is a very good cleaner in itself. But it is strong 
and must be used with care because it is also a good paint remover. 
If the workers are not careful and splatter it against the wall, the 
wall paint starts peeling off. 


Also when trisodium phosphate is used, it must be buffered care- 
fully to prevent crystallization. When this phenomenon occurs and 
the compound goes out of solution, crystals are formed and remain in 
the cracks of the floors. This crystallization develops great force, and 
will chip and spoil your floor. 

Aside from finding the right compound, the next important thing is 
to buy mops with care. The average user will call up and say, "Send 
me a mop stick." There are five-foot mop sticks and seven-foot mop 
sticks. To bring costs down, get the long one. It is obvious that a 
man swinging the longer mop covers more ground over a wider arc and 
gets more done quicker. 

The maintenance of composite floors, such as asphalt tile and 
linoleum, is a very large field, and much can be said about it. One 
must be very careful with asphalt-tile floors. Too many floors have 
been ruined by using the wrong type of wax and solvents. Asphalt 
tile has become very popular. It is made out of the end products of 
the destructive distillation of petroleum, and hence soluble in most 
organic solvents. 

When a floor of this type is waxed a water-emulsion wax must be 
used. Carbon tetrachloride, for example, cannot be used to take out 
stains as asphalt is soluble in this and other organic cleaners. These 
floors can be hardened by mopping with just salt water. Bleeding, 
meaning the colors starting to blend together and becoming a sort of 
amorphous color rather than a well-defined one, can be stopped by 
using certain acids. Vinegar has been found to be an excellent acid 
for the purpose and easily obtained. 

Marble floors present other problems. For example, a very strange 
thing happened at LaGuardia Field when the author's company took 
over the maintenance of the International Air Terminal. It was found 
that the floor became dirty quickly. It was a nice, red Tennessee- 
marble floor that had been treated so brutally that it was white, 
bleached. Too strong detergents had been used on it, and when a 
marble floor is too clean, the first person who walks on it leaves marks. 
It was necessary to dirty the floor a bit to bring it back to its nice red 

Red Tennessee marble is a very common floor covering in lobbies. 
It should be pinkish, and the way to get it pink, if it is white, is not to 
wash it for a while, just let it get good and dirty. If it is desirable to 
keep up the appearance a bit, wash it with water only and mop it. 
As a matter of fact, this is an excellent way to clean a floor. If enough 

446 FRAAD 

water is put on a floor, most of the dirt will float off. Of course, the 
surface-tension reducing agents in water softeners help. 

Some may ask why all this fuss about mopping a floor. This is 
perfectly natural if you have only small areas and little usage with 
which to contend.' 

Maintenance and cleaning always have been the forgotten and 
neglected factors in most business operations, but in recent years, 
there has been a decided change-over from the assignment of misfits 
and failures in other departments to the maintenance and cleaning 
chores. Business executives have found that it makes a decided 
difference in the profit-and-loss columns if maintenance problems are 
handled with as much thought and research as are given to other 
business problems. 

Therefore, with regard to hard floor coverings, have an intelligent 
person carefully study your cleaning operations for three or four days. 
Have him check the cleaning compounds used to be sure that they are 
the right ones for the type of floors. Make sure that the mops and 
other equipment utilized are as efficient as possible and better floors 
and a less-expensive operation, irrespective of the area you have to 
keep in condition, will result. 

Theater Engineering Conference 

Floor Coverings 

Note: At the request of Chairman A. Griffin Ashcroft, all discussion was 
held until the sixth and last paper in this group was presented. The ma- 
terial that follows, therefore, is in the nature of a panel or round-table dis- 


MR. WADE: Mr. Beckwith, I am interested in knowing a little more about the 
qualities of this rubber lining. The name "sponge" is used, and that to my mind 
brings up the natural sponge which is quite water-absorbent. I imagine the name 
was just accidental rather than well thought out. I believe, from your descrip- 
tion, this material is not water-absorbent. Is that correct? 

MR. O. P. BECKWITH: I anl not a rubber expert, so I cannot answer that, but 
I think the gentlemen from the United States Rubber Company can. I do not 
believe the sponge rubber absorbs water at all like natural sponge which we get 
from the sea. It is just a term used to describe the structure of the rubber itself 
which does look like a sponge. But I do not think whether or not it will absorb 
water would be too much of a problem in a theater, do you? 

MR. WADE: In general, no, except for areas around water fountains where you 
might get a little splash, and then pass the water into the base of the rug. 

MR. LLOYD JANTZEN: Answering your question as to the reason the word 
"sponge" is employed, that has probably been in existence for 25 years. Sponge 
rubber as such was developed in Europe about that number of years ago, and the 
structure of the stock itself appears spongy, similar to a marine sponge. It has a 
tendency to absorb moisture. 

This particular class of sponge is highly absorbent (referring to foam rubber). 
The class of sponge that is used for undercarpets is only partially porous, within 
the stock, but as I stated earlier, the surfaces are impermeable, which means that, 
they are absolutely airtight. No water can pass through the surface. 

They can be cleaned. We do not recommend that they be swabbed by pouring 
water too freely on them, but they can be cleaned with a damp mop. You will 
find that the water will remain on the surface, and not go into the sponge in this 
undercarpet sponge. However, if this were used (referring to foam rubber), we 
do not, of course, recommend this. I only brought this along to show the contrast 
between foam rubber and sponge rubber. This material is used entirely for seat- 
ing, mattresses, and pillows, because it dissipates body heat completely and 
entirely. That would not be a practical product for carpet cushioning. It does 
not have the tensile strength that the other does, nor does it have the abrasive 
resistance that this has. This is designed for the undercarpet job. 

MR. WADE: In some of these sponge or foam rubbers there is a sort of recovery 
time. Whereas I do not think there is any actual flow of the material, there seems 
to be a sort of viscosity associated with some of the sponge or foam rubbers. Is 
there anything like a viscosity constant qf any value associated with this material 
used in undercarpets? 



MB. JANTZEN: I have never run across anything like that. 

MR. WADE: Does it recover practically immediately from any deformation? 

MR. JANTZEN: That is correct. It is merely a case of taking a steel plate and 
putting the rubber on it and pounding it for all you are worth with a hammer, and 
its recovery is immediate and complete. 

MR. ZARO: Mr. Savoury recommended that rubber floor coverings not be laid 
on grade since I inferred no cement has been found which will retain the rubber to 
a cement slab on grade. On the other hand, Mr. Jantzen, in discussing the 
sponge-rubber underlay, made mention of fastening the sponge rubber to the sur- 
face with an insoluble water cement and binding the edges. 

We have done a lot of experimenting and I have had considerable correspond- 
ence with your company on just this sort of thing. I wonder if you can explain 
that point to me. 

MR. JANTZEN: Your question has to do with the type of bonding agent to use 
for bonding the sponge rubber to a cement floor? 

MR. ZARO : That is right. 

MR. JANTZEN: My experience has shown that the usual water-soluble type of 
glue employed for cementing linoleum to floors is also satisfactory in applying this 
to cement floors as well. 

MR. ZARO: Actually we have used at least ten different types of adhesives 
and in each case eventually the rubber has crept. That was another question I 
wanted to ask. How actually could you prevent the rubber from creeping? You 
made mention of the fact that the rubber would grip the carpet, but in using a rub- 
ber underlay or floor covering in an aisle, where you have a certain amount of 
elevation, you do get a great deal of creeping. So far no one has ever explained to 
me what I could use or what could be used to eliminate it. 

MR. JANTZEN: That has been one of the features of bonding the quarter-inch 
sponge rubber to the floor and then placing the carpet immediately over it, 
anchoring it at the edge in the conventional way where you anchor your carpet to 
the floor with the studs in the usual fashion. The nature of the sponge rubber is 
such that usually it does not skid on any kind of smooth surface even if not bonded. 
I do not know how to demonstrate that to you. Let us take a sheet of steel for 
example. You cannot make the rubber skid. As a matter of fact, this materia 
in three thirty-seconds of an inch is usually sold as a nonskid underlay for scatter 
rugs. It serves no cushioning value. It just serves as a nonskid agent. 

MR. ZARO: I can understand that on a flat area, but where you have an area 
where you have a definite incline, you do get a certain amount of creep in the rub- 
ber itself. 

MR. JANTZEN: You mean if the rubber were cemented to the floor? 

MR. ZARO: Yes. We have found that the rubber will not stay cemented to 
the floor. 

Mr. JANTZEN: That might be entirely due to the cement that you have used. 

MR. ZARO: Can you recommend a cement since I have not been able to find 
one yet? 

MR. JANTZEN : I think so. 

MR. ZARO: Then may I go back to Mr. Savoury to ask if you have found a 
cement which is satisfactory, why you do not recommend using the rubber sheet- 
ing that you mentioned or the rubber tile on slabs which are not on up grade. 

1948 DISCUSSION 449 

MR. TOM SAVOURY: We are talking about two different things. I mentioned 
the fact that it is not recommended to apply any hard tile; what we call a hard 
tile is a sheet-rubber flooring or a blocked tile or below grade. Actually in the 
industry we have not found a cement that would keep the flooring down for any 
length of time that would be profitable to use it that way. 

Probably there is a way of attaching sponge undercarpet padding for the pur- 
pose, but they are two different problems. Is your problem one of keeping the 
sponge underlay, where you have a carpet, in place or is it to put down a rubber 
flooring such as a sheet flooring or a tile floor? 

MR. ZARO: It seems to resolve itself into the same problem, in that the rubber 
sponge will not adhere to the floor. 

MR. SAVOURY: Probably Mr. Jantzen can amplify this a little better. So far 
as we are concerned, wherever we are required to apply a rubber flooring, one that 
has no relation to carpets or to sponge, whenever the areas are on or above grade 
where there is no space underneath it to aerate it properly, there is no cement on 
the market that will keep it down. That is quite positive. 

MR. ZARO: I realize this is very costly, but it has been recommended to me to 
use copper sheeting between the slab and the rubber. Do you known whether or 
not it actually is successful? 

MR. SAVOURY: Yes, we have installed several jobs in Florida. My company 
has actually put down slab copper that is very thin; I believe it is called an elec- 
trolytic copper. That is put down with an asphalt emulsion, and over that is 
cemented the rubber flooring. That can work, but it is really a very scientific 
and difficult job to install, but it has been done, and it is kept in place. 

MR. LEONARD SATZ: Mr. Smeallie mentioned that humidity control is desir- 
able in the preservation of carpet. That is, controlled humidity. Am I correct 
in assuming that? 


MR. SATZ: Do you understand that the majority of our air-conditioning sys- 
tems are not centrifugal-type cooling systems, in that we use well water? For 
that reason, we remove as much humidity from the air as possible in order to intro- 
duce comfort into the auditorium. We do not have true air conditioning, really, 
in the average theater installation in that we do not return through the air a 
proper or controlled amount of humidity. We remove as much of it as we can. 
Under those circumstances, I take it the air-conditioning system means nothing 
in the preservation of the carpet. 

MR. SMEALLIE: It would not add anything. In wool the water content is 
great and the variation probably up to one fifth of its weight. You can see how 
quickly the lack of density would allow for wear. 

MR. SATZ: Is there a greater weight of wool per given area for a five-frame 
Wilton than there is in a three-frame Wilton? 

MR. SMEALLIE: That, of course, would depend upon the height of the pile. 

MR. SATZ : All factors being equal. 

MR. SMEALLIE: You get only one yarn in the surface to form the pattern, 
while the others would lie buried in the body and the back, and the more frames 
you add the more varied your surface yarn. 

MR. SATZ: How about the weight of the wool, the weight of the yarn in the 
given area of carpet, pitch and height of pile being equal? 


MR. SMEALLIE: The more frames you use the more would be buried, because 
each frame is not used in the surface to effect the pattern. The others in turn 
would be buried in the full warp length. 

The only thought I want to convey there is that the yarn used in the pile surface 
has the greater length. The buried yarns would only run the straight length of 
the fabric, but for every frame added you would add to the wool basic weight in the 
body, and the back of the fabric. That is why so many carpets in the Wilton 
field would be, say, two and a half or three and a half frames against perhaps a 
household quality that might be considered practical in a full six-frame. If you 
can accomplish your pattern, not bury too much surface yarn, and make it up per- 
haps with a lesser cost in your stuffer yarn, you would accomplish the same thing 
and would have relatively less wool weight in the per yard or similar specifica- 

MR. SATZ: Would you consider it important, in so far as wear is concerned, 
that most of the weight of the yarn in a five-frame Wilton would run underneath or 
through the backing, as compared to a carpet that has most of the pile above the 

MR. SMEALLIE: I do not think there would be great added wear value, except 
it is a softer yarn than those generally used as stuffers. You must have a definite 
amount of body and so-called stuffer warp, but I think you could readily get 
beyond the practical side if you wanted to get a full-frame fabric without accom- 
plishing the design. 

MR. BECKWITH: In the Wilton weave, as was brought out by the comments 
that have passed between Mr. Satz and Mr. Smeallie, in order to achieve pattern 
effects, the amount of yarn used in the surface will vary. In a five-frame Wilton, 
the yarn used in weaving the pile surface will be greater than in a two-frame 
Wilton; however, the amount woven into the nap or surface remains the same. 
Thus, as the number of frames increases, the proportion of the pile surface yarn to 
the total pile yarn decreases, and, in the case of a five-frame Wilton, runs approxi- 
mately 50 per cent. 

On the other hand, in other weaves, such as the Velvet and the Axminster, you 
have about 95 per cent of the total yarn appearing in the surface. It has been our 
opinion in the Smith mills that the amount of wear that is obtained is not very 
greatly affected by the amount woven into the back as occurs in the Wilton, but 
I think there probably is some cushioning effect. 

CHAIRMAN ASHCROFT: In connection with Mr. Satz's question on humidity, 
it might be commented that the experience of the testing laboratories has indi- 
cated that the wear life is increased as humidity rises; that is, as the amount of 
moisture in the air is increased. This is in nearly direct proportion, that is, it is a 
straight-line picture. We are comparing in these instances dry indoor winter 
heating conditions and moderate humidity, not high humidity. 

I should hazard a guess that the average theater humidity probably does run 
up around 40, 45, 50 per cent, even when the moisture is relatively removed by 
the system, and in that case I think Mr. Smeallie's comment is justified. If it. 
ran at 20 per cent humidity as may exist in the average home, you would have a 
distinct difference in life. 

MR. JAMES FRANK, JR.: Apparently one of the places where carpet wear is 
most serious in the theater is on the stairs, and Mr. Beckwith told us about the 

1948 DISCUSSION 451 

fact that wear depends to a great extent on the density. And yet on the stairs we 
normally take the same carpet that we put elsewhere in the theater and we bend 
it over so that we obviously are materially reducing the density on the edge of 
the stair tread where the greatest wear occurs. 

In one of the Society's committees we have talked about this for a long time, 
but just to get it on the record, I should like to know whether any consideration 
has been given or can be given to a special type of carpeting for the stairs with a 
much heavier density, so that when it is bent over it still will give the same kind 
of wear that you would get on the flat surfaces in the theater. 

You might also comment on preformed carpets for stairs, so that if it were prac- 
ticable for the sake of economy you would have your very heavy density in certain 
portions of a 27-inch strip of carpet where it would be bent over and the rest of it 
would be the normal density. 

MR. BECK WITH: It is possible mechanically to do what you say, to weave a 
carpet of different density which might be so woven as to fit the contour of the 
stairs and to Jiave at the edge of the stairs areas of varying density, but I think the 
cost of making such a carpet would preclude its use in theaters. 

Then, your first point about using a carpet on the stairs of differing density 
from that on the other surfaces, or one which would have a density at the nose 
equivalent to carpet on the level can be answered by stating that I think most 
manufacturers have several grades of floor coverings which might be suitable for 
different conditions of theater use. 

For example, we have one particular grade that is used in many theaters, but we 
also have another grade that is even higher in density, and it would seem to me 
that your problem would be to place on the stairs the carpet of higher density and 
on the level, the carpet of lower density. 

MR. FRANK: That is an answer, providing that one of two things is done. 
Either that the theater owners are convinced that a special pattern is required 
to minimize hazard on the stairs and therefore that the pattern of the carpet on 
the stairs has no relation to the other carpet, or that the same pattern is available 
in both qualities of carpet, so that if a man wants to forget about the hazard prob- 
lem or considers that it is not serious, he can have uniform design in both places. 
I do not know that that has been done so far as regular pattern carpet in the thea- 
ter is concerned. 

MR. BECKWITH: It is perfectly feasible to do exactly what you say, to have 
this higher density or higher wearing grade of the same pattern exactly as that 
used on the surface. It is wholly a question of merchandising and sales. If 
sales wants to do that, and they have enough demand for it, they do it, and if the 
problem exists in large enough areas to warrant it, they will do it. 

MR. FRANK: I do think that perhaps conferences and discussions such as this 
may help to create a demand for that if it is the right thing to do. 

CHAIRMAN ASHCROFT: As I recall it, the noses of stairs and the location of the 
wearing surface, where it is the most severe, is at the start of the curve downward 
and never very far on to the maximum curvature. Therefore, I should hazard the 
guess that the difference in density occurring there is a very small difference at that 
particular point, granted that at the exact nose, the outer nose, it is considerable. 
MR. FRANK: That is all right, but then I would say that the heavier density 
would still probably give longer life on the stairs itself, because it is where your 


foot hits the floor on the step, I grant you, that you get the greatest wear. Is 
it not true that if you had heavier density you would have longer wear? 

Mr. Beckwith, can you give us, as the result of the test you discussed before 
very briefly, some very definite recommendations as to the best method of instal- 
ling carpet on stairs? There is quite a variation. We have, as everybody prob- 
ably knows, a number of different ways of attaching the carpet to the stairs, but 
it seems to me that there must be one or two recommended methods, and I think 
we ought to have that in our records, too. 

MR. BECKWITH : We have had some experience with stair-carpet installation 
in theaters, and it has been our opinion and our recommendation as the result of 
these studies in several theaters in the metropolitan area, that in principle we 
should use approximately a 64-ounce felt-hair underlay. This would be used on 
most of the tread portion of the stair, and then at the area covering the nosing, we 
would have a few inches of sponge rubber. We have used products of different 
manufacturers, du Pont, for example, and Sponge Rubber Products, and we would 
recommend a strip about two or three inches in length which would be cemented 
on the tread of the stair, and the sponge rubber would then overhang the edge of 
the nose. 

We have used linoleum cement for fastening the underlays in those installations, 
and then the carpet is laid over that. In some of the installations where we have 
run experiments, we have seen used an oak slat which is fastened to the stairway 
this happened to be a marble stairway that I am thinking of now and that was 
fastened by appropriate expansion nuts. Then the carpet was fastened to that 
tacking strip or slat, and no underlay was used on the riser portion. 

This particular installation which we considered a recommended installation for 
one involving severe traffic, had the carpet fastened on the tacking strip not by 
the use of the customary carpet tacks but by the use of screws and washers, rather 
small ones, and not unattractive in appearance. 

With such an installation, of course, you have the area of the carpet that re- 
ceives the most wear protected by the most resilient and longer wearing underlay, 
that is, the sponge rubber, and you use a minimum amount of the sponge rubber, 
because the sponge rubber costs more than the other types of underlays. There- 
fore you would not use it for covering the whole stairs, particularly in the balance 
of the tread, where the 64-ounce felt will do just as well. 

With such an installation, you have a very permanent fastening of the carpet. 
No doubt it has been the experience of many theater operators that stair carpet 
fastened in the conventional manner, that is, tacked to the tacking strip, often- 
times pulls away, and in that case you have looseness developing and a potential 

In general we should recommend the use of sponge rubber at the nose in mini- 
mum amount, the use of 64-ounce felt for the balance of the tread, a very adequate 
tacking strip, and a very good fastening to the tacking strip. 

CHAIRMAN ASHCROFT: Do you wish to mention provision for moving the car- 
pet in order to get the greatest economy in use of the carpet? 

MR. BECKWITH: I rather took that for granted, but I believe it should be 
standard practice anyway in the installation of carpet on the stairs to leave enough 
at the top so that as the carpet covering the stair nosing gradually wears out, 

1948 DISCUSSION 453 

you can then shift the carpet so that the area which was on the nosing is then 
moved to the point of intersection of the tread and the riser. 

MR. JANTZEN: What did you have in mind in relation to the difference in 
thickness between the 64-ounce felt and the thickness recommended according to 
your ideas of the sponge rubber on the nosing, where you evidently splice the two 
products in order to abut them or overlap them? In other words, in 64-ounce 
you probably would be resorting to about a half-inch thickness of sponge rubber 
to balance in with that thickness of Ozite or felt. Is that correct? 

MR. BECKWITH: Yes, we should use a one-half-inch sponge rubber approxi- 
mately, and that is perhaps a little bit thinner than the 64-ounce felt, but with a 
little traffic the condition is equaled out by the 64-ounce felt diminishing in 

MR. JANTZEN : Mr. Beckwith mentioned something about a firmer density of 
sponge rubber. There is available for stair nosing a sponge rub'ber in a firmer 
density than is used elsewhere, perhaps, as an underlay, and if there is any ad- 
vantage to a firm density of sponge rubber, that is available in any thickness rang- 
ing from three thirty-seconds on up. 

MR. SMEALLIE : I should like to volunteer the thought that for better types of 
theaters or theaters with large budgets, it is very possible to use the Chenille 
weave and break it the wrong way. Chenille is an Axminster weave with the 
cross rows very much pronounced, but if you order it the reverse way and break it 
with the weft direction, you see you have a remarkable edge standing a great deal 
of wear through the sense of the density factor that has been brought up. There 
is a very pronounced advantage in it. Different weights of Chenille for some of 
the larger and finest hotels and theaters have been accomplished, and according to 
price, it costs about 10 per cent more to weave it so wide and so short in length. 
The minute you have a width of, say 30 feet, and only weave it three feet long, 
there is an added cost in production, as you might see, but it is a very valuable 
suggestion in a better budget situation to order the Chenille in the reverse fashion, 
order the length with the width and break it where the weft is shown here against 
any ordinary opening of the usual carpet form. 

MR. FRANK: To my surprise I ran into a theater owner who almost insists 
that we install carpet in the standee portion crosswise and bind it to the carpet 
lengthwise that runs down an inclined aisle. I think that it ought to also go on 
record as to what is the proper way of installing carpet in the auditorium, and the 
reasons for it, if Mr. Beckwith would be good enough to tell us that. 

MR. BECKWITH: I am not too familiar with-that problem. The standard prac- 
tice in the standee portion is to have the carpet laid lengthwise to the length of the 
house, is it not? We have no real data in the laboratory as to the effect of wearing 
of the carpet across the surface in -the manner that you are talking about there. 
I do not know whether it will affect wear so much as it will affect the appearance. 

Laying the carpet crosswise to the direction of traffic might, it seems to me, re- 
sult in these troubles with shading of which anyone familiar with floor covering 
is aware. Whereas, if the carpet is laid so that its lengthwise direction is in the 
same line as that of the traffic, you would not incur those troubles in shading. 
That is just a guess on my part. 

MR. PAUL GARST: The most desirable method of laying the standee carpet is 
to follow out the aisle wherever possible. However, in numerous installations it is 


more feasible to treat the standee separately and in this case it is necessary to butt- 
joint the aisle carpet to the standee carpet. We fully appreciate that this ex- 
planation is not concise enough but, on the other hand, we must bear in mind the 
peculiarities of each theater. Very often by extending the aisle where the standee 
is narrow it runs to quite a loss in matching. This calls for extra carpet, the 
initial cost of which is very high, and thus increasing the over-all cost of the in- 
stallation. By treating the standee as a separate room, using the width for the 
length much of the waste for matching is eliminated and if a careful butt joint 
is made the wear should prove very satisfactory. 

A friend of mine in the theater business who has had a great deal of experience 
with carpets brought up the subject about surface shampooing, and so far no one 
has mentioned that. 

MR. BECKWITH: We are considerably interested in methods of care and main- 
tenance of floor coverings, and particularly in the problem of taking care of floor 
coverings that are wall-to-wall installations and that cannot be removed and 
brought to the rug-cleaning establishment for cleaning. 

Cleaning in a cleaning establishment is the ideal way to take care of floor cover- 
ings, because the floor covering there can be treated with soap and brushed and 
thoroughly rinsed and washed out. You cannot take up carpet that is tacked 
down wall to wall, and when you clean it in a wall-to-wall location you cannot 
apply soap indiscriminately and rinse it out and remove it. 

If I talk first about the difficulties of floor cleaning it may be helpful. The 
application of soap to the pile of the fabric represents a difficulty in wall-to-wall 
location cleaning, because you cannot adequately remove it, and if you do not 
adequately remove the soap that has been deposited by the cleaner, then you are 
liable to run into trouble, because the soap fats that remain may cause rancidity, 
and they may cause very rapid accumulation of soil after the cleaning so that the 
carpet will look worse in a few days after cleaning than it did before. 

The second problem in floor cleaning is that too much moisture will be deposited 
onto the fabric so that the back wets out. Mildew may develop, particularly in the 
summertime, because the carpet cannot dry out readily because of high humidity. 

The cleaners and the manufacturers of soaps and detergents have done consid- 
erable work toward improving detergents and soaps, and it has been our experience 
and I think that of the rug-cleaning industry as well, that the use of synthetic 
detergents rather than the natural kind of soaps gives a much better cleaning job. 

One reason why it does that is that with most of the synthetic detergents, if 
the water that is used is hard, you do not get the mineral materials in the hard 
water precipitating out on the pile surface, and leaving a scum. With soaps, the 
mineral matter constituting the water hardness is precipitated out and a scum is 
left on the surface, which, although it may not readily be apparent, will cause 
rapid resoiling. With synthetic detergents, that does not happen in general. 

CHAIRMAN ASHCROFT: The problem of on-location cleaning is one that the 
industry has recognized as a very difficult one and for which there is no perfect 

Not only the carpet industry but the cleaners themselves are beginning to be- 
come aware that they should "help to solve this problem. Consequently, during 
the last three months, a committee of the New York Rug Cleaners Institute and 
the Carpet Institute's Technical Committee have met together to lay out a 

1948 DISCUSSION 455 

program of research which will perhaps give a satisfactory answer to on-location 
cleaning. I do not know how soon that answer will be forthcoming. They are 
conducting independently and together a series of experiments. The Committee 
is cleaning the carpets in the Institute offices by several different methods to col- 
lect exact data as to the effect of these different cleaning methods and detergents 
that are used. The Rug Cleaners themselves are also conducting research to see 
if they can set up -a system sufficiently satisfactory to recommend it to theater 
owners and public-building carpet cleaning. 

The two precautions Mr. Beckwith has mentioned are valid, however. If you 
must clean on location, do so with a synthetic detergent which does not leave the 
soap fats, but leaves a deposit; perhaps, that is less serious, more innocuous to 
resoil, and also requires less wetting out of the pile underneath the surface. 

There is one caution which you might keep in mind, and that is that the soil 
which you are removing is on the surface, it is not down in the pile. Along the 
lines of Mr. Fraad's comments, you can do a surface job that is reasonably satis- 
factory, but it requires study and care and special techniques. 

MR. DANIEL FRAAD, JR. : We obtained very poor results from on-location 
cleaning of rugs. We have done a few things, though, that possibly could be made 
applicable to the theater owner. In connection with the runners of airplanes, we 
take them out and instead of vacuuming them we blow through them. We have 
found that that is a very satisfactory way of cleaning. The rug is reversed over 
a grating and compressed air is forced through the back of the rug out to the 
grating, the vacuum attachment sucking away the dust. That method is also used 
in Pullman cars. 

Certainly, from a cleaning standpoint, I should like to see large areas of carpet- 
ing put down so that they can be taken up readily and cleaned. We find in clean- 
ing rugs that the most difficult thing, if you have to put water and soap on them, 
is to get it out. It always gets down in, and the resoiling of the rug is so much 
more rapid that you are better off to leave it dirty. 

CHAIRMAN ASHCROFT: Mr. Smeallie mentioned a newer type of installation 
which makes possible the removal with greater ease of the carpet (these tacking 
strips) , and that is something that perhaps might well be investigated in certain 
areas where traffic is heaviest. It might be possible to remove the carpet with 
greater ease with this particular method which does not employ tacks or screws 
through the carpet, but catches the carpet from underneath with protruding 
brads which makes possible, by a stretching process, the pulling off and replacing 
of the carpet. 

MR. M. J. FESSLER: In connection with your remarks about the Carpet Insti- 
tute carrying on the investigations for cleaning carpet, I might offer a suggestion. 
I think it devolves itself more to a mechanical as well as a cleaning agent, and if the 
Institute could devise a unit that will use a solvent, that could be pushed across 
the floor, as you do with a scrubbing machine, we would have something which 
would leave the carpet clean and last for possibly a year instead of maybe a week. 

In the course of Mr. Fraad's remarks, he spoke of soap as not being the ideal 
cleaning agent because of the fact that concerns like Armour and Wilson and 
other people who sell beef have a surplus of fat and so get fatty acids which are 
saponified into soap, which leave, when used, a thin film on the surface. 

Mr. Fraad, what has been your experience with the vegetable oils as a 


substitute? Have you used any wetting agents in connection with your cleaning? 
Have you also had any experience with such products as Nacconol or Santomerse? 
Most of us understand that cleaning with a detergent or a soap primarily involves 
lubrication and flotation, and in order to obtain an ideal cleaning job, we must 
have something that will penetrate the soil. In these last few years these wetting 
agents have played a great part to reduce labor in the factor of cleaning. 

MR. FRAAD: First of all, so far as the wetting agents are concerned we use 
sodium polyphosphates in quite a few of our compounds. It is very important 
but it must be tempered. You can get too much wetting agent in and hence you 
lose slip. You have to look for the compounding to an organization that will 
compound something that fits your purpose, but you should look for wetting agents 
and surface-tension reducing agents. 

As a matter of fact, for the whole idea of cleaning, we take a soap as we know it. 
If we saponify a fat or a fatty acid, we get a soap. I do not say that soap is not 
good, but I have found that in commercial operations the ordinary saponified oils 
are inferior to the wetting agents, and the surface-tension reducing agents. The 
action of soap is more of an emulsifying reaction rather than a surface-tension 
reducing agent, which the wetting agents, such as trisodium phosphate, are. 

We do use sulfated oils and we find that sulfonated oils are very good. How- 
ever, their cleaning action is very strong. You can bleach to a point that you 
have cleaned too much and that is as dangerous as not cleaning enough because 
the aesthetic effect is very bad. However, you are perfectly right in saying that 
there are certain oils that they are using to great advantage. 

MR. FESSLER: Do you use the sulfated fatty alcohols at any point exclusively, 
or do you use them in conjunction with vegetable-oil soaps? 

MR. FRAAD: We do not use them in conjunction with vegetable-oil soaps. 
What we do is to take a compound like Orvus, which is put out by Procter and 
Gamble, and which is, I think, a fatty alcohol sulfate. We add trisodium phos- 
phate to it and work that way. 

CHAIRMAN ASHCROFT: You might be interested in a test that was developed 
in the laboratory to evaluate the resoiling factors of different fats, fatty acids, 
soaps, and synthetic detergents by casting them out in thin films, that is, evapo- 
rating them out on plates, so that what might be considered the minimum deposit 
of film was left, and then studying the action of that film against powdered char- 
coal, or carbon black, in its retention of that soil, by blowing it over it and then 
removing it by blowing or air pressure. 

We found a distinct difference in the adherence of carbon black, at least, if not 
various other soils, to these different films, and there is no question but that the 
natural fats have greater adherence than the synthetics. 

MR. ROBERT SCHMID : There are many means of sewing carpets, and the prob- 
lem which I should like to bring out for the concern of the carpet manufacturers 
is that in the manufacture of long-pile carpets today there is a tendency to clip 
the side wall and leave a void space at the edge. The machine-sewn carpets have 
a tendency to try to pull this carpet together in order to make up for this lack of 
wool. What happens is that you have a hard or inflexible joint at this place, and 
I think if you will observe various carpet installations, you will see that their 
wear is at the seams in a great many cases, and I think it is due to that fact. 
Have the manufacturers anything to say about that? 

1948 DISCUSSION 457 

MR. BECKWITH: I should not attribute the wear at the seam to the fact that 
there is a clipping of the pile or pile left out as you say at the edge. I attribute 
this wear at the seam to the fact that in the sewing operation you tend to create 
a slight ridge in the surface so that the pile of the carpet right at the seam is 
always slightly higher than that of the surrounding surface, and therefore when 
people walk over it, that area at the seam always gets most of the wear because it 
happens to stick up a little more. 

When I was working for the Army in the Quartermaster Corps, we were very 
much interested in the wear of Army uniforms, and we found, for example, that 
in the case of trousers, wear occurs on the fly because of the fact that the cloth 
covering the buttons is elevated over the rest of the surface, and I think that the 
analogy holds true there in floor coverings at the seams. The pile is elevated 
slightly and therefore it receives the initial wear of the foot before the surrounding 

You will find that that kind of effect will be duplicated if you have a ridge in the 
floor. If you have a ridge in the floor, then you will find that the carpet covering 
the ridge will suffer more wear at that point than in the others. 

CHAIRMAN ASHCROFT : Your question was really directed at the manufacturers 
doing something that would make it possible to have a slower wear at the point of 
seaming, whether or not that is the major contribution to wear by, for example, 
increasing the wool coverage at the edges. I think it is common practice to have 
extra wool at the edges. That is my recollection of the standard practice in nar- 
row carpets. Is that true, Mr. Smeallie? 


MR. SCHMID: I do not believe that is wholly true. If you take a long-pile 
carpet in a light fabric, and if you take a moderate hand-sewn machine, one that 
does not exert too much pressure at the joint, and you sew it so you have a flexible 
joint at that point, that carpet will not match. The point is you are either going 
to raise a ridge and have the seam close, or you are going to lay the carpet where it 
will wear the longest and have a line showing. 

Optical Sound-Track Printing* 



Summary It is well known that the nearly universal practice of printing 
sound tracks by contact on the periphery of a rotating sprocket introduces 
significant amounts of flutter, and also amplitude modulation of the higher 
frequencies of the record, principally at the sprocket-hole frequency. 

An optical one-to-one ratio printer in which the negative and the printing 
stock are driven separately by good constant-speed mechanisms has given 
substantially improved quality in printing 16-mm sound tracks. In contact 
prints of 7000-cycle records it is easy to demonstrate rapid fluctuations' of 
output level of the order of 6 to 8 decibels. In optical prints from the same 
negatives such fluctuations do not exceed Va decibel. High-frequency re- 
sponse is improved, to the extent of 5 decibels at 7000 cycles. The cross- 
modulation cancellation density for variable-area track prints is increased by 
about 0.1 in the region of practical interest. Listening tests show an im- 
mediately noticeable improvement in quality when optical prints are com- 
pared with contact prints made from the same negatives. 

The optical system for sound-track printing must be able to resolve pat- 
terns several times finer than the highest frequencies on the sound negative, 
and, for printing on color films, must be especially free from the higher-order 
chromatic aberrations, secondary spectrum and chromatic variation of spheri- 
cal aberration. Ordinary photographic lenses are unsuitable. One sys- 
tem which meets the requirements using commercially available microscope 
lenses is described. 

DURING THE PAST twenty years motion picture sound engineers 
have expended a great deal of effort in improving the me- 
chanical performance of recorders and projector soundheads, in im- 
proving high-frequency definition of optical systems, and in reducing 
the distortions inherent in amplifiers and in light modulators. During 
this same period almost no change has been made in the methods 
and equipment used for printing sound tracks. This is, in a way, a 
remarkable tribute to the basic excellence of the Bell and Howell 
Model D Printer and its close descendents, the Bell and Howell Pro- 
duction Print